Far East Russian nickel sulphide developer
Amur Minerals has a 100% interest in the Kun-Manie project in the north-east corner of the Amur Oblast in Russia’s Far East. Notwithstanding a pre-feasibility study (PFS) completed on the project in 2007, Amur has continued with exploration activity and, to date, has delineated a resource of 155.1Mt of ore containing 1,157kt of nickel or 1,600kt of nickel equivalent (NiE), making it the largest undeveloped nickel sulphide deposit in the immediate environs of China, Japan and Korea. In April 2015, Amur reported that it had completed the first of two internal assessments for developing the project by any one of four methods, from 1) a concentrate for third-party toll smelting, 2) owner-operator smelting in an electric arc furnace to produce a low-grade matte, 3) production of a high-grade matte via the addition of an oxygen plant, a converting furnace and an off-gas converter to the electric arc furnace, and, finally, 4) an option to refine the nickel to cathode precipitate metal via the addition of an electro-winning refinery to the plant. Amur was awarded a production licence by the Russian government in May 2015, but has since continued its exploration programmes ahead of producing either a Russian (TEO) or western feasibility study prior to development.
Valuation: Base case 15c/share to 46c/share depending on scenario
Based on the updated operating parameters implied by the most recent technical and economic studies, Edison estimates equity valuations for Amur, dependent on the actual development option chosen, as follows:
Exhibit 1: AMC equity valuations by development scenario (US cents per share)
|
Valuation* (US cents per share) |
Required equity funding** (US$m) |
Toll smelting |
15 |
138.1 |
Low-grade matte |
27 |
148.4 |
High-grade matte |
26 |
148.4 |
Refinery |
46 |
149.3 |
Combined*** |
26 |
149.3 |
Source: Edison Investment Research. Note: *Calculated using a 10% discount rate applied to dividends. **Equity funding required to achieve maximum leverage ratio (defined as net debt/[net debt+equity]) of 80%. ***Two years of concentrate production for toll smelting, followed by one of low-grade matte production and one of high-grade matte production before achieving full production of refined nickel cathode in year 5.
A key factor in determining our ultimate valuation for Amur is the degree of future equity funding of capital expenditure. In the event of zero equity funding (ie debt funding alone), these valuations increase to 45c for the toll smelting option, 105c for the low-grade matte option and 200c for the refinery option.
Sensitivities: More sensitive to funding mix than to nickel price
In quantitative terms, a 10% change in the nickel price results in a 7-9c change in valuation (for all development scenarios), whereas a 10% change in costs results in a 2-3c change in valuation.
Financials: Net cash funds another field season
Amur had US$5.4m of net cash as at 30 June 2017 after US$2.8m of cash outflows over the course of the first six months of the year. We estimate a further US$1.3m of cash outflows in H217, resulting in US$4.1m of net cash as at 31 December 2017 – sufficient for almost one more field season and associated studies prior to development financing and capital expenditure towards the end of FY18.
Company description: Far East nickel developer
Amur Minerals has a 100% interest in the Kun-Manie project in the north-east corner of the Amur Oblast in Russia’s Far East. The Kun-Manie project encompasses a 36.2km2 area within the 950km2 Kun-Manie exploration licence area and is located 700km north-east of the capital city of Blagoveshchensk on the Chinese border.
Exhibit 2: Kun-Manie location
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In April 2004 ZAO Kun-Manie, a wholly owned subsidiary of Amur, was granted an exploration licence to explore for nickel and related metals, including copper, cobalt, palladium and platinum, in the Kun-Manie licence area. Amur commenced seasonal field work (running from June to October) on the licence in 2004 and issued a JORC-compliant statement in 2007 covering three deposits located on the 40km-long Kurumkon trend, namely Maly Kurumkon, Vodorazdelny and Ikenskoe.
In November 2007, consultants SRK completed a pre-feasibility study (PFS, see page 6 below) for Amur, concluding that a project designed to produce a nickel concentrate had a net present value of US$89m at a discount rate of 10% and nickel and copper prices of US$7.50/lb and US$1.50/lb, respectively.
Since 2007, exploration and drilling has been conducted on an ongoing basis and an updated resource estimate was compiled in late 2013 (and subsequently upgraded in April 2015, March-April 2016, February 2017 and March 2018), which included two additional deposits on the trend – Kubuk and Gorny.
In 2008, Kun-Manie was designated a Federally Strategic Project according to the 2008 amendment of Russia’s subsoil law, the practical relevance of which is that ‘strategic’ projects must complete exploration activities before a production licence can be granted. To this end, a new protocol established that this exploration phase had now been completed.
In June 2014, Amurnedra (a sub-agency and regional representative of Rosnedra, the state licensing agency) completed its review of Amur’s exploration activities and subsequently issued a protocol confirming that the initial exploration phase of the Kun-Manie project had indeed been completed and that the company had met its obligations in the 950km2 licence area under the terms of its original exploration licence – a key precursor in the conversion of a Federally Strategic Project held as an exploration licence to that of a production licence. In particular, the protocol confirmed that Amur had completed sufficient and substantial work to identify a 36.2km2 area of economic interest, which supported the boundary limits for the mining application. In addition, it confirmed that the area located outside the area of mining interest had also been sufficiently explored, which allowed Amur to return 913.8km2 of unwanted territory, which no longer warranted any further expenditure, to the Russian government.
As the initial exploration phase of the project had, at that point, been completed, the way was paved to progress to the next phase of development under the Russian system, namely a detailed exploration and production assessment of the project, conducted under the terms of a new production licence (see Permitting section, below). Note that, although the Russian licensing process is lengthy, Amur reports that it has found it to be both explicit and navigable.
SRK pre-feasibility study (PFS)
In late 2007, the design, configuration and economics of a project at Kun-Manie were outlined in a pre-feasibility study (PFS) undertaken by SRK Consulting (Russia), based on the resources defined to be present in a portion of Maly Kurumkon, Vodorazdelny and Ikenskoe at the time. The study indicated that the defined mineralisation could support three open-pit mines; that subsequent treatment of the (sulphide) ores could be achieved by conventional crushing, grinding and flotation; and that the final concentrate would be suitable for contract smelting, with Amur receiving an estimated 70% of the value of the nickel and 50% of the value of the copper contained in concentrate (note that no payable value was attributed to cobalt, platinum and/or palladium by-products).
Assuming production and processing at a rate of 4.0Mtpa over a 10-year life, SRK estimated production of c 15,900t Ni and 4,300t Cu in concentrate pa and a project net present value (discounted at 10%) of nearly US$89m at nickel and copper prices of US$7.50/lb (US$16,538/t) and US$1.50/lb (US$3,308/t), respectively.
All costs were included in the analysis, including staff costs, mining, transport to and from site, loading and railway transport to the third-party smelter. However, potential cobalt, platinum and palladium co-product revenues were excluded from the analysis. In addition, while the optimal pit outlines were determined, these were not specifically translated into optimum production schedules. As a result, some higher-grade production was delayed until later years, resulting in a reduction of the project’s NPV compared to an optimised result.
In its conclusion to the 2007 Technical Study for Kun-Manie, SRK listed seven points requiring further work, two of which related to the resource. The first related to the grade of the resource and recommended further investigation of the potential to mine a higher grade in earlier years. The second stated that Amur should look at the potential to define additional resources at the project. Also, as announced on 18 May 2012, metallurgical test results conducted by SGS Minerals demonstrated a beneficial reduction in magnesium oxide (MgO) levels globally from 16% to c 11.5%. SRK’s remaining points related to the cost of a process plant, royalty rates and tax holidays and further investigations into site access roads.
Developments subsequent to the PFS (2007)
Work subsequent to the PFS substantially modified the original design concept of the project. Among other things, this included improved metallurgical recoveries and a more than doubled resource base, improved Russian taxation and royalty structures and reduced smelter penalty fees, all of which conspired to necessitate a comprehensive review of SRK’s original specification.
In August 2014, Amur updated the defined reserve at Maly Kurumkon-Flangovy, Vodorazdelny and Ikenskoe-Sobolevsky. The cumulative contained proved and probable reserve was estimated to be 39.2Mt ore containing 219,000t Ni and 58,100t Cu. The reserve was based on JORC 2012 reporting standards and a nickel price of US$8.50/lb (US$18,740/t) and was derived from SRK resource models. Runge, Pincock, Minarco (RPM) then uploaded the resource models to the Whittle open-pit optimisation algorithm in order to generate a series of open-pit mine shells for two distinct scenarios:
■
Existing reserves, based on the promotion of mineral inventory from the existing measured and indicated resource categories into the proven and probable reserve categories.
■
Upside potential, based on the inclusion of inferred resources as well. These pit shells were inevitably much larger than the reserve shells. Nevertheless, a comparison of the two also allowed Amur to determine where in-fill drilling was necessary to convert inferred resources into the higher-quality resource categories for subsequent inclusion in reserve statements.
The generated shells for each of the two scenarios were derived from conventional parameters, such as pit slope angles (45), mine dilution (5%), Q214 operating costs estimates, metallurgical recoveries (80.4% Ni and 90.2% Cu) and metal payability (70% Ni and 50% Cu, but 0% for Co, Pt and Pd). In the process of conducting its study, RPM also confirmed that there was potential to mine some of the ore in the lower levels of the pits by underground methods and that the open pits might well therefore be reduced in size to give an overall ratio of 50:50 of ore from underground vs open-pit sources.
The changes to the design along with inflation and the devaluation of the rouble at that time also resulted in the need for a comprehensive update of operating costs. In Q115, Amur calculated operating costs using first principle engineering practices. The updated Q115 operating costs for both underground and open-pit operations at that time are shown in Exhibit 8 below.
Exhibit 8: Kun-Manie open-pit and underground unit cost estimates (US$)
Cost centre |
Open pit |
Underground |
Mining cost per tonne |
1.58 |
11.88 |
Processing cost per ore tonne |
10.38 |
10.38 |
Tailings handling cost per ore tonne |
0.14 |
0.14 |
Concentrate transport to rail per ore tonne |
1.72 |
1.72 |
General & administrative per ore tonne |
2.15 |
2.15 |
Rail transport to smelter per ore tonne |
12.09 |
12.09 |
Smelter penalties per ore tonne |
3.80 |
3.80 |
Source: Amur Minerals 2015
Note that, over the then projected 15-year life of the operation, approximately one half of production was anticipated to be derived from open-pit sources and one half from underground sources.
The mineralisation at Kun-Manie is sulphidic in character and independent studies by both Russian (Sibsvetmetniproyect) and western (SGS) metallurgical contractors have indicated that it can be recovered into concentrate using historically proven, simple flotation recovery methods. On 10 May 2012, Amur announced the results of flotation test work was undertaken on 24 sulphide ore samples representing six grade ranges taken from the drill reserve portions of the Maly Kurumkon, Vodorazdelny and Ikenskoe deposits. Importantly, the samples selected for SGS’s flotation testing were considered to be more representative of life-of-mine operating parameters and the likely variability of the ore delivered to the process plant than those originally used by SRK. A comparison between the two is shown in Exhibit 9 below.
Exhibit 9: Change in metallurgical recoveries
Metal |
Average life-of-mine grade |
SRK utilised metallurgical recovery (%)* |
SGS projected metallurgical recovery (%) |
Change (%) |
Nickel |
0.57% |
75.9 |
77.8 |
+2.5 |
Copper |
0.15% |
72.9 |
90.4 |
+24.0 |
Cobalt |
0.01% |
57.0 |
68.6 |
+20.4 |
Platinum |
0.13g/t |
51.1 |
73.9 |
+44.6 |
Palladium |
0.14g/t |
40.8 |
82.4 |
+2.0 |
Source: Amur Minerals. Note: *2007 pre-feasibility study.
As a result of the improved recoveries, SGS was able to project markedly higher potential nickel and copper concentrate grades of 9.6% (vs 7.0% used in SRK’s 2007 PFS) and 2.9% (vs a 2.4% life-of-mine average), respectively.
The corollary of increasing concentrates payability was a reduction in the concentration of penalty elements. Two of the most important such compounds with respect to nickel processing are arsenic (As) and magnesium oxide (MgO). In this case, a significant reduction of MgO was achieved by SGS, with levels reduced from 16% (that used in the 2007 SRK pre-feasibility study) to below 11%. However, accurate assessment of the positive impact of any reduction in MgO content on cash flows will only be known after further work has been undertaken by Amur’s consultants. In the meantime, it is known from previous drill programmes that Kun-Manie nickel ores are relatively free of arsenic; however, accurate assessment of arsenic levels will still need to be calculated for the purpose of agreeing any future third-party smelting contract.
Conceptual open-pit study (2015)
Taking into account all of the above developments, in 2015 Amur conceived a conceptual open-pit study based on a modified design for the development of Kun-Manie.
Compared to the three pits proposed in the PFS, Amur’s Conceptual open-pit study in 2015 proposed deriving production from four open pits located along the Kurumkon Trend plus two underground mines. Whereas the PFS projected a throughput rate of 4.0Mpa, this was expanded to 6.0Mtpa to produce 350,000t concentrate pa (albeit via fundamentally the same process route of crushing, grinding and floating the sulphide ore). The recovery of nickel was estimated to be 80% of the mine delivered grade of 0.57% nickel. Copper recoveries were projected to be approximately 90% with a grade of 0.15%. Mill tailings were to be stored in an impoundment area adjacent to the mill site.
Four options for project development
At that time, specific metallurgical test work required to assess the final configuration of the operation had yet to be determined. However, metallurgical test work completed by SGS indicated that it would also be possible to generate a near-final marketable matte and/or smelter product. On 16 April 2015, Amur reported that it had completed the first of two internal assessments for constructing an owner-operated smelter in lieu of contract smelting Kun-Manie concentrate. The study envisaged the smelter being situated on the Baikal-Amur railway line near Verknezeisk or Gorny to simplify the importation of associated consumables (eg coal and limestone). As a result, four potential development options were conceived, reflecting four different, potential end products:
■
Concentrate for third-party toll smelting.
■
A low-grade matte (approximately 25% combined nickel, copper and cobalt) by smelting the concentrate in an electric arc furnace to produce a product suitable for on-sale and future smelting and refining.
■
Alternatively, the low-grade matte could be further upgraded into a high-grade matte via the addition of an oxygen plant, a converting furnace and an off-gas converter to the electric arc furnace. In contrast to the 25% of combined metals in the low-grade matte, the high-grade matte would contain approximately 70% combined nickel, copper and cobalt and would (typically) be sold to a refinery for onward processing.
■
The final product – a cathode precipitate metal – would be produced by the addition of a refinery to the circuit, comprising leaching, solvent extraction electrowinning (SX-EW) and precipitation plants. In this case, the recovered metal would include nickel and copper cathodes, cobalt precipitate and platinum and palladium metals.
Economically, the development of an on-site smelter would obviate the US$12.09/t expense of railing concentrate to a third-party toll smelter, but would incur additional smelting and refining costs. At the time, the blended average operating cost per tonne over the life of the operation was estimated to be US$34.86 per ore tonne, as shown in Exhibit 10 below.
Exhibit 10: Kun-Manie open-pit and underground unit cost estimates (US$)
Cost centre |
Owner operated smelter option |
Mining cost per tonne |
9.10 |
Processing and tailings cost per ore tonne |
10.51 |
Concentrate transport per ore tonne |
1.72 |
General & administrative per ore tonne |
2.26 |
Rail transport to smelter per ore tonne |
0.00 |
Smelter penalties per ore tonne |
0.00 |
Smelting cost per ore tonne |
11.27 |
Total cost per ore tonne |
34.86 |
Cost centre |
Mining cost per tonne |
Processing and tailings cost per ore tonne |
Concentrate transport per ore tonne |
General & administrative per ore tonne |
Rail transport to smelter per ore tonne |
Smelter penalties per ore tonne |
Smelting cost per ore tonne |
Total cost per ore tonne |
Owner operated smelter option |
9.10 |
10.51 |
1.72 |
2.26 |
0.00 |
0.00 |
11.27 |
34.86 |
Source: Amur Minerals, 2015
Note that, in the case of Amur developing on owner-operated smelter, it would also benefit from the absence of toll smelter payability deductions (estimated at 30% for nickel and 50% for copper) and allow it to manage its own magnesium oxide balance. Potentially, it would also provide Amur with the opportunity to toll smelt on behalf of other third parties with excess concentrate with access to the Baikal-Amur railway line.
Including owner-operated smelter options, capital expenditure estimates for the four development options were as follows:
Exhibit 11: Kun-Manie conceptual open pit study 2015 capex estimates (US$m)
|
Toll smelting |
Low-grade matte |
High-grade matte |
Refinery |
Initial |
Sustaining |
Initial |
Sustaining |
Initial |
Sustaining |
Initial |
Sustaining |
Infrastructure & permanent facilities |
|
|
|
|
|
|
|
|
Studies |
5 |
0 |
5 |
0 |
5 |
0 |
5 |
0 |
320km access road |
312 |
7 |
312 |
7 |
312 |
7 |
312 |
7 |
Power |
118 |
3 |
118 |
3 |
118 |
3 |
118 |
3 |
Site facilities |
10 |
0 |
10 |
0 |
10 |
0 |
10 |
0 |
EPCM (road, power facilities) |
6 |
0 |
6 |
0 |
6 |
0 |
6 |
0 |
Processing |
133 |
4 |
133 |
4 |
133 |
4 |
133 |
4 |
Tailings |
14 |
23 |
14 |
23 |
14 |
23 |
14 |
23 |
Electric furnace smelter |
0 |
5 |
127 |
5 |
127 |
5 |
127 |
5 |
Converter smelter |
0 |
3 |
0 |
3 |
190 |
3 |
190 |
3 |
Refinery |
0 |
3 |
0 |
3 |
0 |
3 |
342 |
3 |
Smelter infrastructure |
0 |
0 |
22 |
0 |
22 |
0 |
22 |
0 |
Haul roads |
10 |
20 |
10 |
20 |
10 |
20 |
10 |
20 |
Ikenskoe diversion |
0 |
0 |
0 |
0 |
0 |
2 |
0 |
2 |
Total fixed assets |
608 |
68 |
757 |
68 |
947 |
70 |
1,287 |
71 |
Mobile equipment |
|
|
|
|
|
|
|
|
Transportation fleet |
15 |
29 |
15 |
29 |
15 |
29 |
15 |
29 |
Mining fleet |
79 |
150 |
79 |
150 |
79 |
150 |
79 |
375 |
Total mobile |
94 |
179 |
94 |
179 |
94 |
179 |
94 |
404 |
Grand total |
702 |
247 |
851 |
247 |
1,041 |
249 |
1,381 |
475 |
Source: Amur Minerals, 2015. Note: Totals may not add up owing to rounding.
The original concept was always for the flotation concentrate to be trucked 320km from site to the rail head at Ulak located on the Baikal-Amur railway for onward transportation by rail to a commercial smelter. However, since Amur was looking at developing an owner-operated smelter, the road design was similarly upgraded to handle year-round operations, being widened to two lanes with an increase in the size of the associated maintenance fleet.
In contrast to the earlier PFS, Amur’s conceptual open-pit study assumed that power was to be generated on site using diesel generator sets as opposed to via an extension of the grid, thereby obviating c US$288-360m of power line construction costs. This marked a substantial change from the scenario envisaged at the time of SRK’s PFS, when the local utility stated that a power line would be constructed at its own expense. A total of 40MW of installed capacity was planned. Alternatives, such as wind, hydroelectric, etc, were also considered.
In May 2015, Amur announced that it had obtained a 112km2 water allotment adjacent to the planned mill site at Kun-Manie. The water allotment area included the Maia River and eight of its drainages and was examined using various geophysical survey methods and subsequently drilled (c 20 holes of 100m each, on average) to determine the sources from which water may be extracted (including the provision of potable water to support a 1,000-person operation). Studies included an assessment of ice formation and its thickness and impact on the availability of water. These surveys also provided valuable information in establishing permafrost limits and depths.
Developments post the conceptual open-pit study
Two important developments subsequent to the conceptual open-pit study in 2015 include the first production-scale metallurgical test work performed by Gipronickel in 2017 and ongoing exploration by Amur in the Kun-Manie licence area.
Metallurgical test work results
On 11 January 2017, Amur announced the results of Gipronickel’s metallurgical test programme on a c half tonne sample of ore derived from half core from three drill holes located at Maly Kurumkon-Flangovy (representing 60% of Kun-Manie ore by tonnage).
The Gipronickel results marked the first production-scale test work from the Kun-Manie licence area and, owing to their larger size, were therefore presumed to be more reflective of the actual production process than those calculated from SGS’s bench-scale tests. Prior flotation test work on the sulphide ores by SGS was concluded on 12 samples covering six incremental grade ranges distributed throughout the JORC-drilled areas of MKFL and Kubuk. The results of these tests were released to the market in August 2016 for a 0.7% nickel grade (calculated as an average of recoveries from 0.6% Ni and 0.8% Ni) and are compared to the Gipronickel results for the half tonne bulk sample (actually 443.9kg), which had an actual nickel grade of 0.7% (see Exhibit 12, below).
Exhibit 12: MKFL metallurgical recovery comparison, Gipronickel vs SGS (%)
Recovery (%) |
Nickel |
Copper |
Cobalt |
Platinum |
Palladium |
Silver |
Gold |
SGS (average recovery at 0.7% Ni grade) |
69.2 |
77.9 |
53.3 |
49.5 |
58.3 |
49.5 |
53.4 |
Gipronickel (0.7% Ni grade) |
80.6 |
83.8 |
61.4 |
59.6 |
82.3 |
70.5 |
63.7 |
Difference (percentage points) |
+11.4 |
+5.9 |
+8.1 |
+10.1 |
+24.0 |
+21.0 |
+10.3 |
Source: Amur Minerals, Edison Investment Research
In addition to issues of comparability with SGS’s result, the 0.7% Ni grade of the half tonne sample also approximates the 0.75% Ni average grade of the mineable reserve calculated by RPM in its open-pit/underground production trade-off study. Notwithstanding its larger size, recoveries from the Gipronickel half tonne sample were self-evidently materially higher than the results achieved by SGS. In part, this may be attributed to the fact that the SGS test work involved coarse pulverisation of the samples and included older material that was likely to have partially oxidised, resulting in lower recoveries. In addition, Gipronickel employed a two-stage grinding process such that, after initial grinding and concentrate generation, the reject stream was reground to allow for the recovery of a second concentrate.
Ongoing analysis of the metallurgical characteristics of the Kun-Manie ore bodies by Gipronickel is in the form of the processing of a 7.5t bulk sample recovered in the 2016 drill programme. In the meantime, the Gipronickel results also indicated a higher recovery to concentrate in the form of a higher mass-pull than previously calculated and higher concentrate grades of 8.58% Ni and 2.10% Cu. This created the potential for a consequent reduction in fleet transport and in infrastructure capex (eg via a smaller concentrate treatment facility) and for additional capex savings (eg via the requirement for a smaller flash furnace) in the event that Amur opted for a matte or refinery development option.
However, it should be noted that Amur will have to undertake additional work programmes, involving drilling pre-resource exploration targets and laboratory test programmes for these increased concentrate grades to be deemed applicable to Kun-Manie as a whole.
RPM open-pit/underground production trade-off study
Amur’s metallurgical test work announcement followed the release of the results of a trade-off study between open-pit and underground mining, conducted by RPM in late December, which identified a potential mineable reserve of 44.5Mt of ore at grades of 0.75% Ni and 0.19% Cu at MKFL (cf a mineable reserve of 45.5Mt identified in Amur’s preliminary economic assessment [PEA], at an average grade of 0.53% Ni and 0.15% Cu). Key differences between the RPM study and the original PEA are a materially higher underground component of the overall mining operation and materially higher grades overall, as shown below:
Exhibit 13: RPM mining trade-off study results compared to original PEA
Area |
Parameter |
RPM study |
PEA |
Change (units) |
Change (%) |
Underground |
Ore (Mt) |
31.7 |
28.1 |
3.6 |
12.8 |
Ni grade (%) |
0.79 |
0.49 |
0.30 |
61.2 |
Cu grade (%) |
0.19 |
0.15 |
0.04 |
26.7 |
Open pit |
Ore (Mt) |
12.85 |
17.4 |
-4.55 |
-26.1 |
Ni grade (%) |
0.63 |
0.59 |
0.04 |
6.8 |
Cu grade (%) |
0.18 |
0.16 |
0.02 |
12.5 |
Total |
Ore (Mt) |
44.5 |
45.5 |
-1.0 |
-2.2 |
|
Ni grade (%) |
0.75 |
0.53 |
0.22 |
41.5 |
|
Cu grade (%) |
0.19 |
0.15 |
0.04 |
26.7 |
|
Contained Ni (kt) |
332.2 |
241.0 |
91.2 |
37.8 |
|
Contained Cu (kt) |
83.5 |
69.3 |
14.2 |
20.4 |
|
Waste |
43.7 |
47.3 |
-3.6 |
-7.6 |
|
Strip |
3.40 |
2.73 |
0.67 |
24.5 |
|
Ni to conc (kt) |
251.7 |
192.8 |
58.9 |
30.5 |
|
Cu to conc (kt) |
65.4 |
62.4 |
3.0 |
4.8 |
Source: Amur Minerals, Edison Investment Research
The RPM study assumed that the nickel and copper were together recovered into an aggregate 2.5Mt of concentrate (ie a 5.6% mass-pull) containing an average of 9.9% Ni and 2.9% Cu (ie based on SGS, rather than Gipronickel, grade-recovery curves). In addition, the RPM study was conservative in that it assumed Western Australian underground mining costs, contributing to a total operating cost of US$40.02 per ore tonne. It also did not include the results of the 2016 field season.
As stated previously, up until late 2016, Amur calculated its reserves at Kun-Manie with reference to Australian, rather than Russian, underground mining costs. In order to correct this obvious overstatement, in late 2016, the company commissioned RPM to prepare an independent review of projected operating cost estimates, which the latter duly completed in July 2017, as follows:
Exhibit 14: RPM operating cost estimate summary
Cost centre |
Units |
Open pit |
Underground |
Mining costs |
|
|
|
Open-pit mining |
US$/t waste |
1.60 |
|
Open-pit mining |
US$/t ore |
1.73 |
|
Average open-pit mining (3:1 strip ratio) |
US$/t ore |
6.53 |
|
Average underground mining |
US$/t ore |
|
7.44 |
|
|
|
|
Processing costs |
|
|
|
|
US$/t ore |
0.72 |
0.72 |
|
US$/t ore |
2.82 |
2.82 |
|
US$/t ore |
2.72 |
2.72 |
|
US$/t ore |
0.42 |
0.42 |
|
US$/t ore |
4.06 |
4.06 |
|
US$/t ore |
0.76 |
0.76 |
Total processing costs |
US$/t ore |
11.50 |
11.50 |
|
|
|
|
Total costs |
|
|
|
Mining |
US$/t ore |
6.53 |
7.44 |
Ore transport to process plant |
US$/t ore |
*1.58 |
*1.58 |
Processing cost |
US$/t ore |
11.50 |
11.50 |
Tailings |
US$/t ore |
0.16 |
0.16 |
Concentrate transport to Ulak |
US$/t ore |
1.50 |
1.50 |
General & Administrative |
US$/t ore |
1.98 |
1.98 |
Total cost |
US$/t ore |
23.25 |
24.16 |
Source: Amur Minerals, Edison Investment Research. Note: *From Maly Kurumkon-Flangovy.
These open-pit costs compare to a similar assessment conducted by Amur in Q115, which calculated an open-pit cost per ore tonne of US$20.49 and an underground cost of US$26.37/t – albeit this was based on an assumed room and pillar mining technique, whereas RPM’s assessment assumed a long-hole open stoping (LHOS) technique. Costs were estimated to a ±25% level of accuracy and translate into an average cost of US$1.78/lb Ni in concentrate delivered to Ulak and a cut-off grade (at a nickel price of US$4.00/lb, or US$8,820/t vs a spot price of US$6.00/lb, or US$13,230/t at the time of writing) of 0.29-0.39% (ie less than the cut-off grade used in the mineral resource estimate in Exhibit 4). Finally, the calculated costs imply an incremental stripping ratio boundary of 3.6x between open-pit and underground mining – ie the respective operating costs of open-pit and underground mining favour underground mining at an incremental stripping ratio above 3.6x.
The ore haulage cost estimate of US$1.58/t from the mine to the process plant is based on ore mined at Maly Kurumkon-Flangovy and equates to US$0.15/km. At this rate, the cost from Kubuk to the process plant would be US$2.33/t, from Vodorazdelny it would be US$2.21/t and from Ikenskoe it would be US$1.68/t. In making its estimate, RPM noted that ore haulage costs could be substantially reduced by reconfiguring the system to use off-road mine haulage trucks to dump the ore into stockpiles at the pit berms and/or underground portals and then to use smaller, faster and lower operating cost trucks to transport the ore to the mill (as opposed to using the in-pit mining fleet for the entire route).
Note that RPM’s review was based on a toll smelting conception of the development of Kun-Manie. Hence, there was no consideration of smelter terms, recoveries, charges, payable terms and royalties etc, which will be conducted once detailed schedules of grade and tonnage are known thereby allowing a determination of the final metal content of the concentrate.
Amur’s 2017 field season was originally conceived as a 15,000m drill programme starting on 1 June, but with sufficient supplies to drill an additional 5,000m should time and weather permit, targeting a four kilometre long segment of the 16km Kurumkon Trend. In the event, mild weather allowed the company to commence drilling approximately four weeks ahead of schedule, on 5 May. Of the two company owned rigs, the LF70 was assigned to the Ikenskoe deposit and the LF90 to the Kubuk deposit. From the outset, the twin aims of the programme were the conversion of 15.6Mt of inferred resources into the indicated category and resource expansion at Ikenskoe and Kubuk.
As in the 2016 field season, an early start date coupled with a high rate of progress in the form of a high drill rate averaging c 135m per day resulted in the drill programme progressing ahead of schedule. As a result, 26,485.6m of drilling was completed during the year (32% ahead of target) within 107 holes (average 248m/hole) at a record low cost of US$34.83/m (direct drilling plus indirect processing) – implying a total cost of the programme of US$0.9m. Key results were as follows:
■
A total of 74 holes (69% of the total) intersected ore grade mineralisation no less than 3.0m in width in excess of 0.4% nickel; the average mineralised thickness per hole was 22.4m containing a length-weighted, undiluted grade of 0.80% Ni and 0.25% copper (ie above the averages of the pre-existing, February 2017 mineral resource estimate).
■
Step out drilling of 13 holes identified 650m of additional new mineralisation immediately to the southeast of the Ikenskoe deposit, approximately doubling its strike length. Drill grades for the new mineralisation were reported to be substantially higher (eg up to 0.98% nickel) than those reflected in the February 2017 mineral resource estimate, while nine holes intersected ore with an average thickness of 33.1m (ie almost triple the thickness of the mineralisation defined in the February 2017 mineral resource estimate). As a result, Amur declared a JORC-defined exploration target in the area of 10-15Mt at a grade of 0.9-1.0% nickel, cf 21.1Mt at 0.69% Ni as at February 2017. Note that, at this grade, the delivered cost of nickel in concentrate to Ulak could be as low as US$1.30/lb (cf US$1.78/lb, above) and could therefore precipitate a significant shift in the anticipated production schedule at Kun-Manie to advance and accelerate production from this area.
■
The Kubuk deposit was similarly extended westwards by approximately 600m, again approximately doubling the size of the deposit, with grades in the order of 0.75% nickel and thicknesses in the order to 19.8m. Note that mineralisation to the east of Kubuk also remains open, at material grades (eg 1.02% nickel), albeit declining widths (eg 3.8m).
■
The majority of the drilling in the 2017 field season (c 18,500m, or 70% of the total) was conducted along 2.4km of the 3.0km geochemical and geophysical anomaly between the Ikenskoe and Kubuk deposits, denoted the ISK zone (see Exhibit 3). In addition to the March 2018 resource upgrade (see Exhibit 16, below), the FY17 drill results confirmed that there is potential for contiguous mineralisation along the entire trend between the two, with the largest continuous thickness of mineralisation in a single hole at Kun-Manie being recorded (namely 76.4m at an average grade of 0.93% nickel and 0.20% copper), such that the whole could comprise a single c 4.5km long deposit. Drilling in this area has recorded an average mineralised interval of 22.9m at grades of 0.80% nickel and 0.30% copper. As a result, the whole area from Ikenskoe to Kubuk is interpreted to contain three large mineralised blocks, separated by two fault zones. Additional prospective exploration ground also exists to the north of this area in the form of a drill hole (completed in 2005) that intersected 11.6m of mineralisation at a grade of 1.28% nickel.
Overall therefore, the FY17 exploration programme expanded the known mineralised strike length within the 4km trend between Ikenskoe-Sobolevsky and Kubuk by an additional 2,250m to a total of 3,650m. A summary of the increase in the strike length of the mineralisation for the three blocks is as follows:
Exhibit 15: FY17 field season extension of mineralised strike length, by zone
Area |
Original length (m) |
New length (m) |
Increase (m) |
Increase (%) |
IKEN |
600 |
1,250 |
+650 |
+108.3 |
ISK |
0 |
1,000 |
+1,000 |
N/A |
KUB |
800 |
1,400 |
+600 |
+75.0 |
Total |
1,400 |
3,650 |
+2,250 |
+160.7 |
Source: Amur Minerals, Edison Investment Research
As a result of the work completed in the 2017 field season, on 20 March 2018, Amur announced an updated mineral resource estimate, as compiled by consultants RPM. As with the previous estimate, dating from February 2017, the resource was calculated at a cut-off grade of 0.4% nickel, such that sub-economic mineralisation is no longer included in the global resource inventory. A comparison between the March 2018 mineral resource estimate and that of February 2017 is as follows:
Exhibit 16: Kun-Manie mineral resource estimate, March 2018 vs February 2017 (0.4% cut-off grade, excluding Gorny)
|
March 2018 mineral resource estimate |
|
Change vs February 2017 mineral resource estimate (units)* |
Orebody |
Tonnage (Mt) |
Ni (%) |
Ni (t) |
Cu (%) |
Cu (t) |
Co (%) |
Co (t) |
Pt (g/t) |
Pt (t) |
Pd (g/t) |
Pd (t) |
|
Tonnage (Mt) |
Ni (%) |
Ni (t) |
Cu (%) |
Cu (t) |
Co (%) |
Co (t) |
Pt (g/t) |
Pt (t) |
Pd (g/t) |
Pd (t) |
Kubuk |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Measured |
0.0 |
0.00 |
0 |
0.00 |
0 |
0.000 |
0 |
0.00 |
0.0 |
0.00 |
0.0 |
|
0.0 |
0.00 |
0 |
0.00 |
0 |
0.000 |
0 |
0.00 |
0.0 |
0.00 |
0.0 |
Indicated |
32.9 |
0.69 |
226,000 |
0.19 |
63,000 |
0.014 |
4,700 |
0.13 |
4.3 |
0.12 |
3.9 |
|
29.3 |
-0.18 |
194,680 |
-0.02 |
55,440 |
-0.002 |
4,124 |
-0.05 |
3.6 |
-0.07 |
3.3 |
Total M&I |
32.9 |
0.69 |
226,000 |
0.19 |
63,000 |
0.014 |
4,700 |
0.13 |
4.3 |
0.12 |
3.9 |
|
29.3 |
-0.18 |
194,680 |
-0.02 |
55,440 |
-0.002 |
4,124 |
-0.05 |
3.6 |
-0.07 |
3.3 |
Inferred |
4.7 |
0.70 |
33,000 |
0.19 |
9,000 |
0.014 |
700 |
0.12 |
0.6 |
0.12 |
0.6 |
|
-6.2 |
-0.04 |
-47,660 |
-0.01 |
-12,800 |
-0.001 |
-935 |
-0.04 |
-1.2 |
-0.02 |
-1.0 |
Total |
37.6 |
0.69 |
257,990 |
0.19 |
72,490 |
0.014 |
5,394 |
0.13 |
4.9 |
0.12 |
4.5 |
|
23.1 |
-0.09 |
146,010 |
-0.01 |
43,130 |
-0.001 |
3,183 |
-0.03 |
2.5 |
-0.03 |
2.3 |
Ikenskoe |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Measured |
10.6 |
0.71 |
75,000 |
0.18 |
19,000 |
0.011 |
1,100 |
0.22 |
2.3 |
0.26 |
2.8 |
|
0.5 |
0.05 |
8,340 |
0.00 |
820 |
0.000 |
-11 |
0.01 |
0.2 |
0.01 |
0.2 |
Indicated |
13.6 |
0.66 |
89,000 |
0.17 |
24,000 |
0.012 |
1,700 |
0.18 |
2.4 |
0.20 |
2.8 |
|
7.3 |
0.05 |
50,570 |
0.03 |
15,180 |
0.001 |
1,007 |
-0.02 |
1.2 |
-0.05 |
1.2 |
Total M&I |
24.2 |
0.68 |
164,000 |
0.18 |
43,000 |
0.012 |
2,800 |
0.18 |
4.7 |
0.23 |
5.6 |
|
7.8 |
0.04 |
58,910 |
0.01 |
16,000 |
0.001 |
996 |
-0.02 |
1.3 |
-0.02 |
1.5 |
Inferred |
27.8 |
0.80 |
222,000 |
0.23 |
63,000 |
0.017 |
4,600 |
0.19 |
5.2 |
0.19 |
5.3 |
|
23.1 |
-0.04 |
182,520 |
0.03 |
53,600 |
0.001 |
3,848 |
0.00 |
4.3 |
-0.04 |
4.2 |
Total |
51.9 |
0.75 |
386,000 |
0.20 |
106,000 |
0.014 |
7,500 |
0.19 |
9.9 |
0.21 |
10.8 |
|
30.8 |
0.07 |
241,430 |
0.03 |
69,600 |
0.002 |
4,944 |
-0.01 |
5.6 |
-0.04 |
5.6 |
Vodorazdelny |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Measured |
0.6 |
0.74 |
5,000 |
0.22 |
1,000 |
0.012 |
100 |
0.29 |
0.2 |
0.32 |
0.2 |
|
0.0 |
0.00 |
0 |
0.00 |
0 |
0.000 |
0 |
0.00 |
0.0 |
0.00 |
0.0 |
Indicated |
3.2 |
0.85 |
27,000 |
0.21 |
7,000 |
0.017 |
500 |
0.16 |
0.5 |
0.16 |
0.5 |
|
0.0 |
0.00 |
0 |
0.00 |
0 |
0.000 |
0 |
0.00 |
0.0 |
0.00 |
0.0 |
Total M&I |
3.8 |
0.85 |
32,000 |
0.21 |
8,000 |
0.016 |
600 |
0.20 |
0.7 |
0.19 |
0.7 |
|
0.0 |
0.00 |
0 |
0.00 |
0 |
0.000 |
0 |
0.00 |
0.0 |
0.00 |
0.0 |
Inferred |
1.0 |
0.81 |
8,000 |
0.22 |
2,000 |
0.016 |
200 |
0.17 |
0.2 |
0.16 |
0.2 |
|
0.0 |
0.00 |
0 |
0.00 |
0 |
0.000 |
0 |
0.00 |
0.0 |
0.00 |
0.0 |
Total |
4.8 |
0.83 |
40,000 |
0.21 |
10,000 |
0.017 |
800 |
0.18 |
0.9 |
0.18 |
0.9 |
|
0.0 |
0.00 |
0 |
0.00 |
0 |
0.000 |
0 |
0.00 |
0.0 |
0.00 |
0.0 |
Maly Kurumkon |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Measured |
0.0 |
0.00 |
0 |
0.00 |
0 |
0.000 |
0 |
0.00 |
0.0 |
0.00 |
0.0 |
|
0.0 |
0.00 |
0 |
0.00 |
0 |
0.000 |
0 |
0.00 |
0.0 |
0.00 |
0.0 |
Indicated |
57.5 |
0.77 |
445,000 |
0.22 |
124,000 |
0.015 |
8,900 |
0.15 |
8.8 |
0.16 |
9.3 |
|
0.0 |
0.00 |
0 |
0.00 |
0 |
0.000 |
0 |
0.00 |
0.0 |
0.00 |
0.0 |
Total M&I |
57.5 |
0.77 |
445,000 |
0.22 |
124,000 |
0.015 |
8,900 |
0.15 |
8.8 |
0.16 |
9.3 |
|
0.0 |
0.00 |
0 |
0.00 |
0 |
0.000 |
0 |
0.00 |
0.0 |
0.00 |
0.0 |
Inferred |
3.4 |
0.80 |
27,000 |
0.22 |
7,000 |
0.017 |
600 |
0.16 |
0.5 |
0.15 |
0.5 |
|
0.0 |
0.00 |
0 |
0.00 |
0 |
0.000 |
0 |
0.00 |
0.0 |
0.00 |
0.0 |
Total |
60.9 |
0.78 |
472,000 |
0.22 |
131,000 |
0.015 |
9,500 |
0.15 |
9.3 |
0.16 |
9.8 |
|
0.0 |
0.00 |
0 |
0.00 |
0 |
0.000 |
0 |
0.00 |
0.0 |
0.00 |
0.0 |
Total measured |
11.2 |
0.71 |
80,000 |
0.18 |
20,000 |
0.012 |
1,300 |
0.23 |
2.5 |
0.27 |
3.0 |
|
0.5 |
0.05 |
8,900 |
0.00 |
500 |
0.001 |
117 |
0.02 |
0.2 |
0.02 |
0.3 |
Total indicated |
107.0 |
0.74 |
787,000 |
0.20 |
217,000 |
0.015 |
16,200 |
0.15 |
16.0 |
0.15 |
16.6 |
|
36.4 |
-0.03 |
247,300 |
-0.01 |
67,400 |
0.000 |
5,762 |
-0.01 |
4.9 |
-0.01 |
4.6 |
Total M&I |
118.2 |
0.73 |
867,000 |
0.20 |
237,000 |
0.016 |
17,500 |
0.16 |
18.5 |
0.17 |
19.6 |
|
36.9 |
-0.02 |
256,200 |
-0.01 |
67,900 |
0.002 |
5,879 |
-0.01 |
5.1 |
-0.01 |
4.9 |
Total inferred |
37.0 |
0.79 |
290,000 |
0.22 |
81,000 |
0.017 |
6,000 |
0.17 |
6.4 |
0.18 |
6.6 |
|
17.0 |
0.02 |
134,560 |
0.01 |
40,120 |
0.002 |
2,875 |
0.00 |
3.0 |
0.01 |
3.3 |
Grand total |
155.1 |
0.75 |
1,157,000 |
0.21 |
319,000 |
0.015 |
23,500 |
0.16 |
24.9 |
0.17 |
26.0 |
|
53.8 |
-0.01 |
390,760 |
0.00 |
109,020 |
0.001 |
8,754 |
0.00 |
8.2 |
-0.01 |
8.1 |
Source: Amur Minerals, Edison Investment Research. Note: *Totals compare to February 2017 mineral resource estimate; M&I = Measured and Indicated. Totals may not add up owing to rounding.
On the basis of our US$0.9m cost estimate above, we therefore calculate Amur’s incremental discovery cost of resources to have been US$2.36 per tonne of contained nickel in FY17 (cf Amur’s current resource multiple of US$29.41/t – see page 6). Note that no resource was estimated at Gorny (similar to February 2017, but in contrast to earlier estimates), on account of its being a relatively small deposit and the only one with an average grade below the 0.4% cut-off grade at the time of the H116 mineral resource estimate. As a result, Gorny has been excluded from the above table, although future drilling could result in its re-inclusion once again, at a later date. Otherwise, the following are noteworthy features of the upgrade:
■
The 51.6% increase in aggregate tonnage in the indicated category (primarily attributable to an 813.9% increase in tonnage in the indicated category at Kubuk).
■
The 85.0% increase in aggregate tonnage in the inferred category (primarily attributable to a 491.5% increase in tonnage in the inferred category at Ikenskoe).
■
The 0.05 percentage point increase in grade in the measured category (attributable to Ikenskoe).
Substantial exploration potential remains untested within the Kun-Manie production licence area. However, now that it is the largest undeveloped nickel sulphide deposit in the Far East, drilling for additional resource expansion is no longer deemed to be a strategic imperative for Amur. As a result, drilling in the 2018 field season will focus on metallurgical drill sample collection to support relevant metallurgical test-work designed to allow the company to refine its process flowsheet in order to:
■
identify the requirements necessary to generate a nickel sulphate product for direct sale to the electric vehicle battery market; and
■
establish the possibility of generating a separate copper concentrate (which could potentially allow Amur to enter into a streaming deal to part fund its initial capex requirements).
Technical and commercial acuity
Throughout the course of the 2017 field season, Amur has made extensive use of its onsite sample preparation facility in tandem with its two handheld Niton XL2 X-Ray fluorescence spectrometers (RFAs). To ensure the accuracy of RFA spectral analysis, the two units are calibrated against existing standards and previously derived Alex Stewart Laboratory (ASL) results. In addition, for QA/QC (Quality Assurance/Quality Control) purposes, Amur’s geological team inserts blind blanks and blind duplicates of samples from within each drill hole and samples from which previously derived ASL results are known. The results from these samples are then monitored by the geological team in order to ensure that the analytical team are generating results to within an acceptable level of accuracy and to trigger an immediate re-assay procedure in the event that results are anomalous. This procedure allows Amur to report grades to the market far in advance of the certified analytical results. In addition, it allows Amur to adjust its drilling programme in a timely fashion to reduce the number of barren holes on the periphery of the ore bodies as well as reducing the number of samples sent away for formal ASL analysis and the number of waste samples in the hanging wall – thereby, incidentally, also improving the turnaround time of samples that do require formal assay and the associated costs as, otherwise, a far greater weight per sample would need to shipped to ASL. Compared to the average US$8.83 that it costs to process and assay each sample using its on-site sample preparation facility in conjunction with its two RFAs, without them, Amur estimates that it would otherwise cost c US$40 per sample. Note that the RFA generated results have demonstrated only very small variations (eg 0.02% Ni and 0.01% Cu) from the certified and independent results.