Dims: 0.16x0.14x0.16" (3.96x3.66x4.01mm)
Wt: 0.75ct (0.15g)
Tschikapa, Kasai Province, Congo
This cube of diamond is a single crystal, and its form is only moderately distorted, being a little tapered towards one end, and one corner seems to be missing (which is unlikely, as it is very difficult to damage a diamond). The real oddity is that in the center of the smaller face are two pits, readily visible with a loupe, which look like crystals of something else had been overgrown by the diamond, and subsequently disolved away. This seems incredibly unlikely to me, but that is what it looks like.