These are stupidly pretty obsidian dice. As we know from Dwarf Fortress, obsidian is an easily accessibly yet very valuable trade good–this is why I bring these dice to the caravan outpost. I've developed a whole floodgate system for harvesting lava flows to drive my obsidian-dice-based economy.
These are Haxtec brand dice made in China. They should come in a little foam lined tin, like a set of fancy ear buds or... Or something clever and funny I can't think of. Fancy candy. Does fancy candy come in a foam lined tin? Oh! Botulism-laden tuna comes in a foam lined tin.
It's the whole polyhedral set but you'll only need the d6 and the d10. Throw the rest in the special trash can you set aside for unneeded dice.
These are a 'gemstone' dice and as such might be fragile. I am going to recommend that you not dump them in a dice bag or roll them on a steel table or whatever. Again–these are actually carved from a mineral dug out of the dirt. Not cast resin.
I don't know how to explain this but these are cooler in person than they are in the picture. The numbers aren't raised at all and the material is...reactive? Absorbent? When you handle them they absorb the oil/moisture from your skin and go a flat flat flat black. Like a void. And then the shiny little numbers are the only way you can see detail. Some of this is a one-way trip because I can see a thumb print on the d20 from when I handled these a week ago.
I'm a sucker for dice and am very pleased with these.