- For the month, see Calendar.
Slate is a metamorphic stone. It should not be confused with slade, an entirely different material.
"Slate" is the name of the second month of the dwarven calendar, covering mid-spring.
In Real Life
Slate is shale which has been metamorphosed at high temperature and pressure. Metamorphic compression causes foliation in slate, called "slaty cleavage," perpendicular to the direction of maximum stress. Slate is frequently grey in color, but occurs in a variety of other colors, such as cyan, green, pink, and purple.
Slate is used to produce roofing slates, a variety of roof tile. Before the advent of synthetic chalkboards, slate was widely used for blackboards and writing slates; these were written upon using a chalk or shale pencil.