If a treasure hoard includes gemstones, you can use the following tables to randomly determine the kind of gemstones found, based on their value. You can roll once and assume all the gems are the same, or roll multiple times to create mixed collections of gemstones.

10gp Gemstones:
d12 = 1

Azurite (opaque mottled deep blue)

10gp Gemstones
d1210gp Gemstones
1Azurite (opaque mottled deep blue)
2Banded agate (translucent striped brown, blue, white, or red)
3Blue quartz (transparent pale blue)
4Eye agate (translucent circles of gray, white, brown, blue, or green)
5Hematite (opaque gray-black)
6Lapis lazuli (opaque light and dark blue with yellow flecks)
7Malachite (opaque striated light and dark green)
8Moss agate (translucent pink or yellow-white with mossy gray or green markings)
9Obsidian (opaque black)
10Rhodochrosite (opaque light pink)
11Tiger eye (translucent brown with golden center)
12Turquoise (opaque light blue-green)