JOHANNESBURG (miningweekly.com) – Aim-listed Botswana Diamonds has started drilling at the Ontevreden kimberlite pipe, which is part of the company’s Vutomi Joint Venture in South Africa and which contains significant quantities of G10 and G9 garnets.
“We are pleased to announce the commencement of drilling at the Ontevreden kimberlite pipe. We know that the pipe contains significant quantities of G10 and G9 garnets, which are high-quality diamond indicator minerals frequently found in high-grade kimberlite pipes. The drilling is to discover diamonds,” Botswana Diamonds chairperson John Teeling commented in a statement released on Tuesday.
Following the discovery of a kimberlite pipe at Ontevreden in July 2017, work was undertaken to ascertain the potential for the pipe to be diamondiferous.
Results from ground samples taken from the pipe were analysed and produced abundant G9, G10, and complementary eclogitic garnets in a mix typically associated with high-grade kimberlites.
Rock geochemistry undertaken by the Council for Geosciences categorised Ontevreden as a Group 2 kimberlite. Detailed ground geophysics have also been undertaken and this identified a minimum surface pipe surface area of 100 m x 70 m.
The drilling operations will confirm the size, provide an understanding of the internal geology and enough samples to enable both petrography and microdiamond analyses, the company explained.
The Ontevreden kimberlite pipe is close to diamond miner Petra Diamonds' now mothballed Helam mine.