|Congo cube diamond.
Congo cubes are really strange objects: pure natural diamond crystal, yet astronomically less expensive than diamonds normally are. (As this was a very generous Christmas present I'm not going to go on and on about how cheap Congo Cubes are, and one this large is actually not all that cheap in an absolute sense, it's just a lot less than the many thousands that a comparable 3 caret single-crystal diamond would cost.)
They come in a wide range of sizes and shapes, but most of them are fairly cubical, which raises the question: Why cubes? The individual crystals that make up a Congo Cube are randomly oriented, so why should the thing as a whole assume a cube shape? I have no idea. It would also be interesting to find out what's inside: Is it dense or are there air gaps or inclusions of dirt? What would it look like if you polished one face of the cube?
Want to find our for yourself? Look up Congo Cubes in google or eBay you'll find all sorts available.
Source: Chris Carlson
Contributor: Chris Carlson
Acquired: 25 December, 2003