Gas rich, ultra-basic diatremes from mantle depths (>30 km)and alluvial placer deposits derived from the Kimberlite rocks. Kimberlite = olivine, garnet, pyroxene, and calcite.
IMA Status:
Valid Species (Pre-IMA) Prehistoric
Locality:
Kimberly, republic of South Africa. India. Brazil. Ural Mountains, Russia. Murfreesboro, Arkansas, USA. Link to MinDat.org Location Data.
Name Origin:
From the Greek, adamas, meaning "invincible" or "hardest."
Chemical Formula: 