Abstract
WE have observed numerous rounded purple isotropic grains up to 100 microns in diameter in thin sections of two stones from the Tenham meteorite shower1 (British Museum B.M.1935,792 and Australian Museum DR 8298). The grains occur chiefly within black veins cutting across the stones, but the same material also replaces olivine within 10–20 microns of certain thicker veins and at the margins of some large chondritic fragments within the veins. Our investigations show that the purple mineral is the high pressure spinel polymorph of olivine, and for this first authentic natural occurrence we propose the name ringwoodite, in honour of the experimental studies2 by Professor A. E. Ringwood, Australian National University. The name covers the entire range of (Mg,Fe)2SiO4 spinels, and has been approved by the Commission on New Minerals and Mineral Names, International Mineral-ogical Association.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
