The slater's stake is a tool for cutting slates to size. It has a sharp straight edge at the top and a sharp point at the bottom that can be hammered into the roof boarding. The slate is placed on the sharp top and cut off with the roofer's hammer.
There are different models: round, triangular, rectangular, straight, curved. The straight models are made entirely of metal and have no handle, while the triangular models have a wooden handle. [MOT]