If you’re tired of run of the mill diamonds and semi-precious stones, jeweller John Bagley offers rings inset with fossilized dinosaur bone, a reddish material that looks to me a bit like both jasper and bloodstone. I am not sure why the material is coloured as it is, but Bagley provides some information (though not about the colour) here. You must create an account and log in to obtain pricing, or so it seems. The ring shown is made with 14k gold.