Magma Floor (IMAGE) University of the Witwatersrand Caption Sketch of an underground exposure in Lonmin Platinum mine, Western Bushveld Complex, showing the development of the Merensky Reef package along subvertical to overhanging margins of a pothole. Such relationships can be best interpreted by in situ growth of silicate minerals and sulphides of the Merensky Reef directly at the chamber floor. Credit Wits University Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.