Natural diamonds are moderately rare, although not as rare as the companies like to suggest. Especially if you want high quality natural diamonds that actually look good.

Apparently mining companies are a bit disinterested in diamonds really. They are quite an ordeal to deal with and to effectively mine. They tend to be bound up in a lot of random junk material, mostly low-grade iron and rock, that you don’t actually want, and don’t really have much use for, and the signal to noise ratio can be quite high.

Although a lot less interesting it’s probably more profitable for a mining company to simply come across a large stockpile of copper, then a possible diamond source. Unless it is unusually pure and high quality.