HomeBase MetalsIvanhoe finds high-grade zinc, copper, silver, germanium below Kipushi mine’s Big Zinc...

Ivanhoe finds high-grade zinc, copper, silver, germanium below Kipushi mine’s Big Zinc resource

TSX-listed Ivanhoe Mines has found additional, exceptionally high-grade zinc, copper and silver drill intercepts in the fourth batch of assay results from its underground diamond-drilling program undertaken at the historic, high-grade Kipushi mine, in the Democratic Republic of Congo (DRC).

Drilling at depth to the south of the Big Zinc zone has revealed a new intersection of massive sulphide mineralization containing sphalerite (zinc), chalcopyrite (copper) and pyrite, Ivanhoe Mines chief executive Robert Friedland and CEO Lars-Eric Johansson announced in a statement.

Hole KPU072 – drilled through the historical Big Zinc zone from the hanging-wall drill drift 1 272 m below surface to test for the depth extension of the Big Zinc to the south – intersected a zone of significant massive sulphide mineralization over a down-hole length of 60 me.

It is, however, uncertain at this stage if the intersection forms a down plunge extension of the Big Zinc zone or is a separate body of mineralisation.

“Our underground drilling program at Kipushi is continuing to deliver exceptionally high-grade intercepts in several target areas, while leading to an improved understanding of geology and structural controls on the mineralisation,” says Friedland.

He goes on to say that the recent intercept in hole KPU072 highlights the potential to discover new zones of high-grade zinc and copper mineralisation and that Ivanhoe Mines is “looking forward to drill-testing these targets as its drilling program continues”.

Highlights of the new assay results include:

  • KPU051 drilled on section line 7:  188.5 m grading 49.7% zinc, 0.3% copper, 15 g/t silver and 58 g/t germanium.
  • KPU055 drilled on section line 7:  162.9 m grading 51.1% zinc, 0.4% copper, 11 g/t silver and 59 g/t germanium.
  • KPU057 drilled on section line 5:  175.7 m grading 50.3% zinc, 0.3% copper, 11 g/t silver and 27 g/t germanium.
  • KPU058 drilled on section line 11:  41.4 m grading 42.1% zinc, 3.8% copper, 54 g/t silver and 71 g/t germanium, including a copper-rich intercept of 6.0 m grading 6.0% zinc, 22.6% copper, 203 g/t silver and 177 g/t germanium.
  • KPU061 drilled on section line 5:  75.6 m grading 46.2% zinc, 0.3% copper, 20 g/t silver and 89 g/t germanium, plus a second intercept of 64.9 me grading 44.7% zinc, 1.1% copper, 14 g/t silver and 128 g/t germanium.

The new assay results also included results in the Série Récurrente (Recurring Series) zone. It included the following significant intercept:

  • KPU049 (Série Récurrente zone):  9.7 m true thickness grading 11.8% copper, 6.0 % zinc and 73.0 g/t silver, including a higher grade intercept of 6.4 m true thickness grading 16.8% copper, 7.7% zinc, 104 g/t silver.

Potential new zone of zinc mineralisation discovered
Ivanhoe’s drilling program now is focused on exploration for new zones of mineralisation below the historical Big Zinc indicated resources.

The first of these holes, KPU072, was drilled to test along the southerly plunge of the Big Zinc.

Mineralisation appears similar in style and zonation to the Big Zinc, with mixed massive red sphalerite (iron bearing), chalcopyrite and minor pyrite from 417.32 m to 420.55 m, massive pale brown sphalerite (zinc rich) from 420.55 m to 468.09 m, and massive pyrite with accessory chalcopyrite and sphalerite from 468.09 m to 477.17 m. The core intersection angles suggest the zone may have a true width of about 30 m.

KPU072 is the second hole to successfully intersect Big Zinc-style massive sulphides at depth. The KPU003 hole also intersected a zone of massive sulphides.

Nord Riche zone tested

Two holes have recently been drilled into the area where the Série Récurrente zone intersects the Kipushi Fault Zone, historically referred to as the Nord Riche (North Rich) zone. Ivanhoe’s holes KPU073 and KPU074 targeted down-plunge extensions of this zone below the level of historical mining. Zones of disseminated and massive sulphides were intersected in both holes, and assay results are pending.

Ivanhoe cautions that the presence of mineralization observed in the three holes — KPU072, KPU073 and KPU074 — is presented to confirm only the presence of mineralisation similar in style to that observed in other holes drilled to date both in the Big Zinc and Fault zones. Assays for copper, zinc, lead, germanium and precious metals for these holes are pending.

Ivanhoe has completed 75 holes, totalling about 14 900 m of its planned 20 000 m underground diamond drilling program.

Assays for holes one through 64 have been released, while assays for holes 65 through 75 are pending.

Two diamond-drill rigs continue to complete exploration and confirmatory drilling of the Big Zinc, Nord Riche and Série Récurrente zones from the hanging-wall drill drift on the 1 272 m level.

About the Kipushi Mine
Ivanhoe Mines’ Kipushi mine is located on the Central African Copperbelt just 30 km southwest of Lubumbashi in the Katanga province of the DRC. Kipushi lies southeast of the company’s Kamoa discovery.

Ivanhoe Mines acquired a 68% interest in Kipushi in November 2011 and has assumed responsibility for ongoing redevelopment, dewatering and drilling. State-owned mining company Gécamines holds the remaining 32% interest.


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Chantelle Kotze
Chantelle Kotze is a Johannesburg-based media professional. She is a contributor at Mining Review Africa (Clarion Events - Africa) and has created content for the media brand over the past 6 years.