This is my absolute favourite set of dice of the many, many, (idiotically) many dice I've ever owned. These are literal gem dice, in that they are cut from actual bloodstone (a semi-precious stone). For complicated reasons (that begin with Judas Priest) bloodstone is my favourite gemstone so finding dice cut from it was a transformative experience for me.
There's a YouTuber I watch who cuts d20s from precious gems people send him (for a price of course) and they look so damn pretty