Petra Diamonds
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ASX-listed Lucapa Diamond Company and its partners have good news regarding their kimberlite exploration program at the Lulo diamond project in Angola.

The Lucapa kimberlite exploration program is designed to identify the primary hard-rock source or sources of the exceptional alluvial diamonds mined at Lulo, the world’s highest average US$ per carat alluvial production.

The Lulo partners are systematically drilling ~80 targets in the current campaign proximal to, and/or upstream of, the alluvial mining blocks.

Drill core from the confirmed kimberlites is progressively logged and exported in batches to laboratories in South Africa and Canada for mineral chemistry analysis.

Lucapa has received the mineral chemistry results from the latest batches of kimberlite core – together with results from historical pit, stream and loam samples sent to the laboratory.

A micro-diamond was recovered from a pit sample at kimberlite L204, which also recorded a strong lherzolitic garnet chemistry signature, which is also closely associated with diamonds.

In addition, diamond-associated G3D, G4D and G10D garnets were recovered from seven Lulo kimberlites, including:

  • Four G4D and one G10D garnet from kimberlite L048
  • Three G4D garnets from kimberlite L050
  • Two G3D and two G4D garnets from kimberlite L232
  • Two G10D garnets from kimberlite target E1921
  • Two G4D garnets from kimberlite L103
  • One G10D garnet from kimberlite L0282
  • One G4D garnet from kimberlite L1043 These eight kimberlites will be the subject of further testing.

The mineral chemistry results from the remaining five kimberlites in the current batches of core to undergo laboratory analysis were of low interest and will not be tested further.

Diamond recovered from kimberlite L104

As set out in the AGM presentation of 24 May 2018, an orange eclogitic garnet and phlogopite in possible mantle xenolith were visually observed in the drill core from kimberlite L104.

This, combined with the presence of historic garimpeiro activity on the kimberlite, prompted the Lulo partners to excavate a bulk sample from L104 to test through the Lulo diamond plant.

A diamond weighing 2.05 carats was recovered from the 614 m3 kimberlite bulk sample.

Kimberlite drilling progress

Further to the ASX announcement of 29 October 2019, the Lulo partners continue to make very good progress with the kimberlite drilling program, which remains on target for completion this quarter.

The Lulo partners have completed drilling 72 targets, of which 53 have been confirmed as kimberlites.

Progress of Lulo kimberlite drilling program, including 11 kimberlites highlighted for follow-up work and 25 confirmed kimberlites to undergo laboratory analysis.

Core from a further 25 targets successfully confirmed as kimberlites is to undergo mineral chemistry analysis.

This includes core already batched and en-route to the South African laboratory; core logged and batched in preparation for export; and kimberlite core recently drilled and, in the core, shed at Lulo.

This leaves just seven targets to be drilled to complete the current campaign, along with any additional proximal targets identified.

Once the drilling of the remaining targets is completed, the Lulo partners plan to conduct a comprehensive independent review of all results received from the kimberlite drilling and sampling completed to date to guide follow-up programs.