Diamond - large octohedral crystal ex. Graw Coll

Item Description

This is a very large, nearly textbook-crystal of octahedral diamond, weighing 6.83 carats. It is glassy but beyond that has the unique bright luster so desirable in diamond - termed as adamantine. Argyll mine has produced some exceptional crystals in recent years, and this style is typical of the production in form but has unusually good, rich cognac color. It is fairly gemmy with translucency or transparency throughout, and a large transparent core. Diamonds of this quality and size are rarely offered for sale by mineral dealers today - this is an older piece from about 5 years ago - and the availability of specimen diamonds from Argyll is predicted soon ramp down with new owners (Rio Tinto) even more intent on mining for gem rough. Anything over 4 carats should be considered a large specimen diamond and this piece, at nearly 7 carats, is a full thumbnail and a beautiful competition-worthy example of a modern Argyll Mine diamond. One of my sources for specimen diamonds has valued similar quality but smaller pieces to me, wholesale if I had to replace it, at $300-500 per carat. So a valuation of $2500-3500 here is not unsupported at all. ex Graw gem crystal collection