The Batu Hitam Prospect, which means 'Black Rock' in Bahasa Indonesia, is another of the main prospect areas within the larger Lakuwahi Project, and is considered, along with the Batu Mas Prospect to be one of Robust's key targets for mineralisation on Romang Island.

Batu Hitam is similar geologically to Batu Mas Prospect geological and mineralisation models in that the gold-silver near-surface mineralisation overlies the primary, polymetallic sulphide, hydrothermal breccia-hosted mineralisation. Additionally at the Batu Hitam Prospect areas of manganese mineralisation occurs as an oxide (dominantly psilomelane) in the very top-most sections of existing drill holes. Some of these intersections are very high grade -- with multiple intersections exceeding 50% Mn.

Diamond drill mineralisation highlights from the Batu Hitam Prospect include holes such as LWD122 which was drilled on the easternmost margins of the Batu Hitam prospect area, and has demonstrated the potential for high-grade gold at depth and under limestone cover. LWD122 intersected a high-grade zone of gold mineralisation at over 100 metres below surface, in primary hydrothermal breccias, LWD122 results include:

• 10m @ 5.15 g/t Au Equivalent (4.88 g/t Au, 13 g/t Ag) from 115m

This is the highest-grade zone of deep, primary gold mineralisation intersected in drilling so far and demonstrates the potential of Lakuwahi for deeper, high-grade precious metal mineralisation. The full geological and economic potential must await additional follow-up drilling although there is a working hypothesis that the mineralisation in this hole may correlate with strong gold and silver discovered in LWD108, located on a section 60 metres west of LWD122. Apart from the potential correlation mentioned above, the result in LWD108 is significant as it conclusively proves high-grade gold and silver mineralisation can develop under limestone cover. LWD108 intersected mineralisation as follows:

• 16m @ 3.10 g/t Au Equivalent (1.42 g/t Au, 81 g/t Ag) from 30m
  • Including 5m @ 5.55 g/t Au Equivalent (3.00 g/t Au, 122 g/t Ag) from 31m