Results from diamond drilling at the Três Estados project in Brazil’s Apuí region have identified consistent platinum group metal (PGM) mineralisation for owner BBX Minerals (ASX: BBX).
The latest two holes to be analysed from the company’s 2020-2021 campaign showed platinum content and local iridium and rhodium values from surface to 31m and for 19.74m to end of hole at 80.74m in hole TED12.
Significant intervals from TED12 were reported according to 5E PGM grades, which refers to the sum of platinum, palladium, iridium, rhodium and gold expressed in units of grams per tonne.
Highlights were 31m at 2.07g/t 5E PGM (1.87g/t platinum, 0.16g/t iridium, 0.02g/t rhodium and 0.02g/t gold) from surface, including 2.69m at 4.35g/t 5E PGM (3.52g/t platinum, 0.53g/t iridium, 0.12g/t rhodium and 0.18g/t gold) from 3m, and 1.65m at 3.44g/t 5E PGM (2.61g/t platinum, 0.72g/t iridium and 0.11g/t rhodium) from 21m.
Also reported was 12m at 1.95g/t 5E PGM (1.79g/t platinum, 0.07g/t iridium and 0.08g/t rhodium) from 61m including 2m at 5.79g/t 5E PGM (5.08g/t platinum, 0.44g/t iridium and 0.27g/t rhodium) from 67m; and 4.24m at 3.47g/t 5E PGM (3.20g/t platinum, 0.08g/t iridium and 0.19g/t rhodium) from 76.5m to end of hole.
However, hole TED11 showed no PGMs and sporadic low gold values, which came as a surprise to BBX chief executive officer Andre J Douchane.
“I have spent a lifetime around this sort of process and intuitively knew that barren holes were not uncommon in any resource evaluation,” he said.
“We conducted a detailed review of the hole’s geology to try and understand how this particular hole could be void and learned that the alteration was very different compared to that of previous holes.”
The alteration style in this hole comprised intense chloritic alteration and carbonate veining, is different from the hematitic alteration style dominant in the remainder of the holes of the campaign.
Although chlorite-carbonate alteration was also found to be present in the mineralised lower portion of TED12, it is reported to be less intense than TED11 and may possibly have resulted in leaching of precious metals.
Mr Douchane said once assaying of the holes at Três Estados and a JORC resource had been completed, the company would turn its attention to the nearby Ema gold project.
“We plan to start assaying drill holes from our 2017 campaign at Ema,” he said.
“I believe everyone would like to know what is there.”