- The Bushveld District of South Africa is the world’s largest producing platinum group elements region, hosting a myriad of high-grade, primarily underground platinum mines that occur along narrow seams called reefs, as well as much larger, polymetallic and bulk mineable deposits including Anglo American’s Mogolakwena open-pit and the more recently discovered Flatreef project being advanced by Robert Friedland‘s Ivanhoe Mines
- The Stillwater District in Montana, USA is well-known for its ultra high-grade J-M Reef which is currently being mined by Sibanye-Stillwater, but the area also shows excellent potential for hosting massive and disseminated Ni and Cu sulphide deposits, enriched in PGEs, chrome and cobalt, similar to the“Platreef-style” bulk minable deposit type
- Group Ten has brought together multiple sets of data that verfiy this. Soil geochemistry and geophysical anomalies are coincident (ie they overlap thus supporting one another) and enormous; rock samples from these areas confirm mineralization at surface and, most importantly, historical drilling which demonstrates thick mineralized intervals starting at surface and running 100s of meters.
- As an indication of metal endowment, grade-thickness at Stillwater West has been shown to range as high as 293 gram-meters total platinum equivalent (TotPtEq). For comparison, the neighbouring Stillwater mines along the J-M reef deposit average approximately 34 gram-meters.
- The Hybrid Zone at Stillwater West is defined by a nearly two kilometre-long soil anomaly. The first 10 drill holes tested an area 600 metres in strike length by 100-200 meters wide and found nearly continuous anomalism to approximately 450m deep; grades approach mineable concentrations over widths of up to 100m. It’s key to note that these were early-stage discovery holes, with no attempt at grade optimization.
- The Hybrid Zone remains open to expansion at depth and in all directions.
- Within the Hybrid Zone, and elsewhere at Stillwater West, Group Ten has identified a number of discordant dunite bodies that range up to 100s of metres across and can boast spectacular rock sample grades. In the Bushveld, and elsewhere, similar rocks occur as clearly defined pipes associated with large-scale, ultra high-grade occurrences (ie Onverwacht, Driekop, Moiihoek).
Group Ten Metals (TSX-V: PGE, OTCQB: PGEZF, FRA: 5D32) is onto something, and they have begun methodically letting the cat out of the bag. In 2017, the Company acquired the polymetallic Stillwater West project in Montana and, not long after, began to publicly compare the geological setting with the northern limb of the Bushveld Complex in South Africa. Specifically, they identify parallels between Stillwater West and Ivanhoe’s massive PGE-Ni-Cu project in the Flatreef area. In what could be viewed as a very compelling endorsement of that position, recently, Dr. David Broughton, former VP Exploration and current Senior Advisor of Geology and exploration at Ivanhoe, joined the Group Ten team after a series of meetings and project visits. Dr. Broughton is, in fact, credited with overseeing the discovery of the Platreef project and the team was recognized with the 2016 Colin Spence Award for excellence in global mineral exploration for their efforts. Still, initially, the comparison with Bushveld sounded ambitious as the Complex is - with numerous producing mines - the world's largest producer of platinum and palladium and covers an enormous tract of land. So, let’s drill down a little further and examine the claims and evidence.
Bushveld Complex is enormous, spanning hundreds of kilometres across but essentially consists of three separate regions or limbs, each of which are somewhat more modest in scale, and host primarily platinum mines that occur along very narrow, high-grade reefs. “The holy grail, and the exploration target for many years, has been to find one of these of these bands to be of a thickness that can be mined quickly and efficiently by modern mechanized mining methods. In Platreef (“Flatreef”) this has now been found.”
Zooming in on the northern limb of the Bushveld, this different type of Bushveld region project can be found – deposits of a broadly disseminated, polymetallic nature that include a suite of base and precious metals set below a concentrated reef. Two projects, in particular, boast size, polymetallic grade and bulk mineability: the Platreef project, the discovery of which netted Ivanhoe’s exploration team a prestigious industry award, and Anglo American’s industry leading Mogalakwena mine (perhaps the touchstone in this regard, a high-grade, open pit operation of massive scale and exceptional economics).
Similarly, Montana’s Stillwater District is primarily known for the ultra-high-grade J-M Reef which hosts the Sibanye-Stillwater mines. As shown below (from the Company presentation), Group Ten holds much of the ground in the Stillwater District that is below the J-M Reef and their property spans some 25 kilometres of strike length. Indeed, their property also includes a narrow slice above the J-M Reef. Known as the Picket Pin deposit, it is another of the narrower reef variety. While this adds further intrigue to the Stillwater West project, we will set it aside for now and concentrate on information publicly disclosed by the Company since acquiring the project in 2017.
What’s important to note is that, as noted above with reference to the analogous Bushveld, the broadly-disseminated deposits of massive scale typically occur below the major reef systems. And that has been the consistent thesis of the Group Ten team over the past 18 months. And now, after extended months of field and desk work, the Company has begun to start publicly presenting their findings: actual numbers and cross-sections that support the notion that their very well might be a Platreef in Montana. To be more accurate, given the enormity of the Stillwater West project and anomalies, there may be EIGHT Platreefs in Montana.
In a series of three, highly-technical news releases since mid-December, the Company has begun to roll out their evidence, systematically moving from west to east across the project. They have announced the existence of eight mulit-kilometre long target areas and, at the time of writing, we have seen information with respect to four. That means there is plenty of substantive news releases ahead. The most recent contains a somewhat overwhelming volume of information that requires a closer look at meaning/implications.
Quoting from President & CEO, Michael Rowley, “Chrome Mountain…is one of our highest priority target areas and has advanced very rapidly with the discovery of a new style of platinum and palladium mineralization associated with nickel and copper sulphides at the Hybrid Zone (see December 17, 2018 news release). This discovery has attracted significant interest in the Stillwater West project with wide intervals of platinum, palladium, nickel, copper, and cobalt mineralization starting at surface, including nine intervals of over 100 meters in thickness with grade-thickness values of more than 100 gram-meter Total Platinum Equivalent (TotPtEq), including six holes which returned composite mineralization of over 200 meters with grade-thickness values of 200 to 294 gram-meter TotPtEq. Grade-thickness values of 25 gram-meter or more are considered economically significant, with the grade-thickness values at the adjacent J-M Reef mines averaging approximately 34 gram-meter palladium and platinum. Values of 100 to 300 gram-meter are exceptional, highlighting the strength of the Stillwater West system.”
To start with, it’s instructive to examine the use of, usefulness of, and indeed meaning of, grade thickness. Put simply, it is a way to compare different projects (whether similar in nature or vastly different) by examining potential contained metal as indicated by drill hole intercepts. A grade thickness number which results from the multiplication of intercept grade and overall thickness, provides a simple orientation over the assumed volume of metal and thus the possible economics of projects. For laypersons and investors, the number takes some getting used to - which could explain, to some degree, why the general market has largely ignored the recent news. For ease of understanding, a 10 gram/tonne intercept of one-meter length. has Grade Thickness of 1 x 10 or 10 gram-metres (g-m). Grades of 5 g/t, but over a two-metre intercept would also yield a Grade Thickness of 10 g-m. In general, a Grade Thickness of 25 is a reasonable early indication of a potentially economic occurrence. NOTE ASSUMPTION BY GROUP TEN OF 100% RECOVERY IN THESE CALCULATIONS
A second concept it is important to briefly touch on, is that of equivalent grades. Essentially, this is an easy way to express the overall grade of a deposit or assay that encompasses all the relevant metals contained therein. Rather than trying to describe a complex, polymetallic result in terms of the individual grades of each metal revealed in the assay, by using relative metal values to ‘convert’ everything to just the primary metal. For example, in a copper-gold project, the overall grade might be expressed in copper equivalent (CuEq) which would use relative metals prices and grade to convert to gold to copper and then add both together. CuEq = Cu grade + (Au grade x Au price + Ag grade x Au price) / (22.0462 x 31.1035 x Cu price. Click here for a handy online metal equivalent calculator.
Ivanhoe Mines uses both grade-thickness and platinum equivalent in their news releases and other public disclosure, as do most mining companies with polymetallic projects. Platreef's full suite (4E plus nickel and copper) grade thickness averages 86 gram-meters platinum equivalent. The project boasts a massive resource of 346 million tons (at 2.0 g / t cut-off) which is entirely hosted in a layer that starts at a depth of approximately 700 metres and with an average thickness of just 19 meters. Compared with most of its Bushveld neighbours, that is shallow and broad. Stillwater West, by comparison, is hundreds of metres thick starting from surface.
Group Ten's grade-thickness numbers leap off the page, even at this early stage. The Company has reported strong drill intervals with platinum, palladium, nickel, copper and cobalt mineralization beginning at surface where 9 intervals had widths in excess of 100 meters with grade thickness values totalling over 100 gram-metres of platinum equivalent. Six holes even delivered more than 200 meters of polymetallic mineralization with grade thickness values of 200 to 294 grams of platinum equivalent (see Table 2). These are enormous targets that already show clear evidence for the type of tonnage global majors are interested in. And again, these were essentially discovery holes which weren’t targeting grade but, rather, mineralization in general.
Furthermore, as described in the above-noted news release, the Company has uncovered a series of surface-expressing dunite bodies hundreds of metres across where “mapping of olivine chromite-rich intrusive returned chip samples of up to 16.0 g/t 3E (as 8.72 g/t Pt, 7.25 g/t Pd, and 0.03 g/t Au) at Dunite Ridge. A second sample at Dunite Ridge returned 7.45 g/t 3E as 2.32 g/t Pt, 5.10 g/t Pd, and 0.02 g/t Au (see Table 2). These samples occur within a highly elevated PGE, Ni and Cu soil anomaly covering at least 750 meters of strike. Intrusive dunites can have spectacular grades in the Bushveld Complex, but have not been systematically explored for in the Stillwater Complex.” In other words, as further evidence of the similarities with the Bushveld, the very structures with essentially led to the discovery of that entire platinum district are present in spades at Stillwater West and none have had drill hole one.
Disclosure: I am/we are long PGEZF.