I have it in my head that diamonds can be analyzed to determine where they came from–I have a notion that it’s based on other chemicals in the diamond. Google isn’t helping though. Is anyone else aware of this and if so how it works? Is any part of the diamond destroyed in the process?
Fluid inclusions may be observed using strong microscopes but you have to section (cut) the crystal to do that. These inclusions are varied, dense, and highly pressurized. In fact, some geologists believe these inclusions may come from the mantle and diamonds are the only minerals strong enough to encapsulate them. As to origin, I’ve a feeling you could only do it for its precise source (which mine.) One guy is looking at the internal pressure of the inclusions to estimate from what depth they formed.
Actually, some people can already deduce megascopically the origin of a diamond (they’re never sure of course.) The De Beers mine produced nice bi-pyramidal ice-white diamonds, while that Australian mine (Argyle??) produced nice colored ones (yellow, blue, red, brandy, etc.)
You might be thinking of Canadian diamonds, which have a tiny polar bear and tracking code burned into them for identification purposes.
This article discusses approaches to fingerprinting diamonds to ascertain the source. When it was written (2003) there seemed to be no good approaches, but I suspect more modern equipment may provide better discrimination - ion microprobes and X-ray fluorescence analysis may allow identification of inclusions.
Some analytical methods are non-destructive, but even destructive methods now rely on very small samples (laser sampled micron sized holes).
Thanks all. Apparently the term of art is “fingerprinting,” searching for “diamond fingerprinting” turns up some good material.
The same applies to gold. Based on the minor contaminants, you can tell which source it was mined from. (I believe this was a plot point in some old thriller novel, where the gold was identified by the authorities as coming from a Nazi stash.) I also saw an article about tracking silver this way, which was used to show that silver in the pre-Roman mediterranean was traded widely across the entire area.