Contributing Editors Emmanuel Fritsch, CNRS, Team 6502, Institut des Matériaux Jean Rouxel (IMN), University of Nantes, France (fritsch@cnrs- imn.fr) Kenneth Scarratt, GIA, Bangkok (
[email protected]) DIAMOND Diamond-bearing eclogite xenoliths from the Ardo So Ver dykes. Specimens of gem diamond crystals in rock matrix are almost never found due to the rigorous processing that occurs during diamond mining. Occasionally, a diamond is found in a sample of the kimberlite host rock that brought it to the surface, but finding a diamond in the rock in which it likely crystallized in the earth’s mantle is ex- tremely rare. When pieces of the mantle break off and are transported to the surface in a kimberlite magma, they are called xenoliths (meaning “foreign rock,” because the man- tle rocks are not formed from the kimberlite magma itself). Recently, five small rock samples containing diamond crystals (figure 1) were sent to GIA Research for examina- tion. The samples were submitted by Charles Carmona Figure 1. These five diamond-bearing eclogite xeno- (Guild Laboratories, Los Angeles) on behalf of owners Jahn liths from the Ardo So Ver dykes in South Africa Hohne (Ekapa Mining, Kimberley, South Africa) and Vince ranged in weight from 2.24 to 12.40 grams, with the Gerardis (an occasional trader and collector of unique dia- largest measuring 2.5 centimeters in length. Photo by monds and producer of the television series “Game of Kevin Schumacher. Thrones”). The specimens were sourced over 25 years ago from a kimberlite fissure mine located 40 miles (65 km) northwest of Kimberley, South Africa.