Alrosa keeps Russian doll-type diamond in rare-find collection
The selection of unique diamonds, Alrosa said on Thursday, already includes skull-shaped and football-like rough diamonds that were mined in recent years.
The latest addition resembles a traditional Matryoshka, or nesting doll, with one diamond freely moving around inside another.
Inclusions and flaws in diamonds are common and most have some kind of flaw, or segments of mineral trapped inside. A diamond within a diamond, however, is something it has never been described before, the company noted.
Even more intriguing is the manner in which the air space formed within the larger stone.
Scientists at Alrosa’s Research and Development Geological Enterprise have put forward various hypotheses of the origin of this diamond. To date, the most probable version is that both internal and external diamonds were formed at the same time, more than 800 million years ago.
Despite its complex structure, the Matryoshka diamond weighs only 0.62 carats (0.124 grams) and measures 4.8 x 4.9 x 2.8 mm.
The internal cavity volume is 6 mm3 and the internal crystal’s volume is 1.6 mm3 with an estimated weight of 0.02 carats (0.004 grams).
The inner diamond has a table shape and dimensions of 1.9×2.1×0.6 mm, Alrosa said.
Alrosa produced more than 43 million carats of diamonds in 2018 from its Russian mines, or about 27% of the world’s total. That’s 18% more than its closest competitor, Anglo American’s De Beers.