RE:RE:RE:RE:RE:RE:RE:KEVIN SMALL DIRECTOR OF RNX FACEBOOK PICS! #5 Gold most commonly occurs as a native metal, but will form compounds (or minerals) with tellurium, sulfur or selenium.
The gold-bearing minerals that contain tellurium are called ‘tellurides’. The Golden Mile deposit in Kalgoorlie, Western Australia, is a massive deposit containing greater than 1500 tonnes of gold.
Some 70 to 75% of gold in the deposit occurs as native gold, but a further 20% occurs as tellurides. The remaining 5 to 10% is in the form of 'invisible' gold that has substituted into the crystal structures of various minerals or occurs as minute particles.
Therefore, extracting gold from telluride minerals, such as calaverite, which contains around 42% gold, has been very important in the history of Kalgoorlie mining, producing around 300 tonnes of gold.