From Ultima Codex
Ultima Online is a special skill, in that it doesn't have skill points. It's just you can or you can't do it. The skill can only be learned after getting 100 points in Carpentry. To learn it, the book "Making Valuables With Stonecrafting" has to be bought for 10.000 gold in Ver Lor Reg on Ilshenar. Once read, the book is destroyed and the skill learned.
To use it, the player needs high quality granite and a mallet and chisel, which also can only be bought in Ver Lor Reg. Most of the items are decorative or furniture, although a special stone armour set exists, complete with a stone sword.