Chalk ground to fine powder by mortar and pestle or in a mill, packaged in a cloth or clay pot for ready use. Scribes and illuminators pounce powdered chalk onto parchment to erase marks; masons mix it with lime and tallow for whitewash and plaster pigment. The powder is light and dry and will cake if stored damp, so it is kept in a sealed vessel or wrapped in waxed linen.
Chalk, powdered
Ground chalk powder in sealed pot; scribes erase, masons whitewash.