WIDESPREAD HIGH GRADE RARE PLATINUM GROUP METALS
CONFIRMED IN LARGE ARC EAST OF BROKEN HILL
New assay data and a review of previous results has confirmed the presence of high grade and
rare platinum group metals in a wide arc stretching from the northeast to the southeast of the
Broken Hill township in far western New South Wales.
The results, from Impact Minerals Limited (ASX: IPT) Broken Hill Joint Venture project in the area,
have demonstrated high to very high grades of the rare platinum group metals (PGM) osmium,
iridium, rhodium and ruthenium at many prospects as well as at the Company’s recently discovered
zones of high grade copper-nickel-PGM mineralisation at the Red Hill Prospect (see announcement
dated 17 April 2015) at the southern end of the arc.
These rare metals – used in many specialist hard-wearing metal alloys, electronics and for catalytic
converters – are currently commanding premium prices – an upside Impact Minerals Managing
Director, Dr Mike Jones, says, could deliver a significant economic credit to any resource defined
within the Broken Hill project.
“These results reinforce our view that Impact’s Broken Hill project contains not just some of the
highest grades of PGM reported in Australia but that they occur over a wide arc where we suspect
even further PGM opportunities will be generated from more detailed surface exploration and
drilling.”
Most of the rock chip samples, which have been variably assayed for the different PGMs, come
from the Moorkai Intrusive Complex in the northern part of the project area where the host
ultramafic unit can be traced for 9 kilometres along trend (Figures 1 and 2).
At the Platinum Springs Prospect at the southern end of the Complex, a representative 120 kg
sample of gossan returned:
19.6 g/t platinum, 50 g/t palladium, 3 g/t rhodium, 3 g/t osmium, 4.4 g/t iridium,
2 g/t ruthenium, 0.57 g/t gold, 0.34% nickel and 0.71% copper;
A nearby drill hole completed by a previous explorer discovered a 2 metre thick zone of fresh
massive sulphide from 45 m depth that returned:
2 m at 52 g/t platinum equivalent comprising 10.9 g/t platinum, 23.6 g/t
palladium, 4.5% copper and 6.1% nickel.
A one metre interval of this was sampled for the rare PGMS and returned:
1 m at 1 g/t rhodium, 1.3 g/t osmium and 1.2 g/t iridium.
At two other undrilled prospects in the Moorkai Intrusive Complex, previous explorers
identified rhodium in grab samples at Round Hill and Back Ridge including respectively (Fig. 1):
5.6 g/t platinum, 8.8 g/t palladium, 0.8 g/t rhodium, 2.4% copper and 0.7% nickel; and
5.2 g/t platinum, 6.5 g/t palladium, 1.0 g/t rhodium, 0.6% copper and 0.1% nickel.
At the undrilled Moorkai Prospect very high grade assays of up to 27.8 g/t platinum, 27.9 g/t
palladium, 14 g/t gold, 9 % copper and 1,8% nickel were returned from gossan samples near
small workings. Although these samples were not been assayed for the rare PGMs, Impact
considers it highly likely that they will contain appreciable amounts of those metals. Further
sampling will be conducted during the upcoming field season.
At the Little Darling Prospect, also not drill tested, in the centre of the Broken Hill Project area a
rock chip sample of gossan returned (Figure 2):
34.8 g/t platinum, 76 g/t palladium, 3.2 g/t rhodium, 1.2 g/t gold, 1.9% copper and
1.9% nickel.
All of these results add to those returned from the Red Hill Prospect at the southern end of the
project where Impact has discovered a 25 to 30 metre thick near-surface layer of copper-nickel-
PGM mineralisation containing two zones of high grade drill intercepts called the Upper and
Lower Zones which returned (Figure 3):
(Note 3PGM = Platinum-palladium-gold and 7PGM = 3PGM + osmium, iridium, rhodium, ruthenium
where assayed (full details in Table 1).
Upper Zone: 9.5 m at 4.7 g/t 3PGM, 1.5% copper and 0.8% nickel including
5.1 m at 11 g/t 7PGM, 1.9% copper and 0.9% nickel (RHD001) and
5.2 m at 7.9 g/t 7PGM, 1.1% copper and 1.6% nickel (RHD006)
Lower Zone: 9.9 m at 6.7 g/t 3PGM, 1.4% copper and 0.3% nickel including
4.2 m at 11.8 g/t 7PGM, 2.6% copper and 0.5% nickel (RHD001) and
13.8 m at 6.6 g/t 7PGM, 1.1% copper and 0.3% nickel (RHD006).
Given that the current spot metal prices in Australian dollars per ounce for these metals are:
rhodium: $1,506/oz; iridium $763/oz: osmium $500/oz and ruthenium $65/oz in addition to:
platinum $1,528/oz, palladium $1,015/oz and gold at $1,581/oz, the rare PGMs may be a significant
economic credit to any resource defined within the Broken Hill project.
Osmium and iridium are used in many specialist hard-wearing metal alloys as well as the
electronics industry. Rhodium and ruthenium are mostly used together with platinum and
palladium for catalytic converters.
Next Steps
Impact has now identified six targets for further drilling at Red Hill (Targets T1 to T6, Figure 4
and see announcement dated 1st April 2015).
Target T1 contains the newly discovered PGM-copper-nickel mineralisation which is interpreted
to dip at a shallow angle to the south, and is close to true width. In addition the mineralisation
may be increasing in width and grade with depth and is in part coincident with an Induced
Polarisation (IP) chargeability anomaly identified in a ground geophysical survey (Figures 3 and
4). IP chargeability anomalies may be associated with disseminated sulphides and magnetite.
Follow up drill holes are required at T1 to test the mineralisation along trend and at depth.
The other five drill targets consist of a ground (T2) and down hole (T3) electromagnetic
anomaly, a rock chip geochemical anomaly (T4), an induced polarisation (IP) anomaly (T5) and
an airborne magnetic anomaly (T6) (see announcement dated 1st April 2015).
The paperwork for the statutory approvals for a drill programme has been lodged and approval
is expected within the next few weeks.
About the Broken Hill Joint Venture Project
Exploration Licence E7390 is owned by Golden Cross Resources Limited (GCR) and is the subject
of two joint ventures, one between GCR and Impact and one between GCR and Silver City
Minerals Limited (ASX:SCI).
Impact has earned 87% of the rights to nickel, platinum and any other metals, occurring in,
emanating from, or which are otherwise associated with, mafic or ultramafic complexes. Should
Golden Cross dilute to less than a 5% interest in these rights then it has to transfer its interest to
Impact for $1 (one dollar).
Silver City has the rights to base metal, silver and gold mineralisation associated with Broken
Hill style mineralisation.
The drill intercepts in RHD001 and RHD006 are the first significant drill intercepts of PGM,
nickel and copper within Impact’s project area away from the high grade drill intercept of 2 m at
6.1% nickel, 4.5% copper, 10.9 g/t platinum and 23.6 g/t palladium in fresh sulphide discovered
some years ago by previous explorers at the Platinum Springs prospect located about 15 km to
the north east. There are many strike kilometres of the same ultramafic host rock that contain
high grade nickel-copper-PGM rock chip assays similar to those at Platinum Springs and Red Hill
that have never been drilled. These results at Red Hill confirm Impact’s belief that there is
potential for a significant discovery near Broken Hill.
Of interest, CRA Exploration completed two diamond drill holes under the Red Hill workings in
1969 with no significant results (Figures 1 and 2). However these holes were drilled from north
to south and detailed work by Impact has now demonstrated that these holes were drilled
parallel to and below the mineralised zone (Figure 2)
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