Diamond miner Lucapa could be closer to locating the source of diamonds found at its Lulo project in Angola.

A recent drilling and sampling program has encouraged Lucapa (ASX:LOM) to undertake follow-up work at an area known as L164 because it has increased “mantle content” and “relatively better, albeit still weak diamond potential”, compared to the other kimberlites already drilled.

Kimberlite is a dark-coloured, heavy rock that contains diamonds and is sometimes found in valuable “pipes” in areas such as the Kimberley district of South Africa.

Kimberlite is named after Kimberley, which was the site of a diamond rush in the late 1800s following the discovery of an 83.5-carat diamond called the Star of South Africa.

Lucapa gained nearly 2 per cent to 26.5c in early Thursday trade.

LOM shares over the past three months.
LOM shares over the past three months.

Lucapa is trying to pinpoint the primary hard-rock source or sources of the “exceptional size and quality” alluvial diamonds being recovered from within the site.

In March, Lucapa netted $2.1 million from the sale of 2072 carats of Lulo diamonds.

The largest diamond in the sale weighed 44 carats, and the most unique was a vivid pink diamond of 1.9 carats. However, that was still shy of its monster 163-carat rock sold for $44 million at the end of last year.

Lucapa said kimberlite L164 produced the highest concentration of G3D and G4D garnets and other kimberlitic indicator minerals of any Lulo kimberlite target tested to date, including 11 garnets classified as diamond-associated grains.

There is also evidence of previous artisanal mining diggings near the target that Lucapa says do not appear to be associated with any extensive alluvial channels.

L164 was highlighted as a large (10-15 hectare) magnetic target in a survey flown over the Lulo concession in 2013 and as a larger electromagnetic target in the subsequent survey flown in 2017.

It is the second Lulo kimberlite highlighted for follow-up work from the ongoing drilling and sampling program.

Consultant Remote Exploration Services recommends Lucapa now undertake micro-diamond sampling or bulk sampling.