Blood Diamonds

[Blodo]

Naturally reddish diamonds are just diamonds that were irradiated during the formation process or afterwards, or have been subjected to larger than usual pressure which misaligned the crystal lattice and gave them a reddish hue as a result of the imperfections. It's a natural process like Dab said.

Anyway the reason why they are called blood diamonds in discovery is not because of slave mining (which is not the case) but because of the bloody conflict in the Omega and Rheinland systems which is systematically ignored by the rest of Sirius and suppressed further by the Rheinland government. Being much rarer than normal diamonds, they are a good source of income for the Hessians as well, and - while being smuggled to Liberty - as a result also for the Unioners and Liberty Rogues.