Yellow-green clinohumite and yellow chondrodite from Tanzania

Abstract

During a buying trip to Tanzania in 2006, gem dealer Farooq Hashmi obtained some brownish yellow and yellow-green rough from a few small parcels that were represented as tourmaline from a new deposit at Sumbawanga in west-central Tanzania. All of the rough consisted of broken pieces (figures 20 and 21), so it was not possible to determine if they originated from primary or secondary deposits. Most of the pieces weighed <1 g, and there was an approximately equal percentage of the two colors available in each parcel. The appearance and properties of the material were not typical of tourmaline normally found in Tanzania, so Mr. Hashmi loaned several rough and cut examples of each color for examination at GIA.

Additional details