Slate Blade
From A Wiki in the Desert
A Slate Blade is a basic blade made with Slate, used in making Boards, Carving, and Slate Shovel.
Use
A Slate Blade is created (Skills → Blades → Knap a Slate Blade) by striking two pieces of Slate together to create one sharpened piece; a process called Knapping.
Two pieces of Slate are required. When Knapping, one of three results is possible, creating a Slate Blade, or failure and loss of one or both pieces of Slate. As your Knapping skill improves, failures are less likely.