A printmaker uses an ink slab, basically the equivalent of a painting palette for printmaking, to mix and roll ink.
Most ink slabs are made out of marble (natural or artificial) or thick chamfered glass (approximately 1 cm thick). Hard, heavy, and resistant to changes in temperature, these materials keep both the slab and the ink stable.
Make sure to keep your ink slab as clean as possible. Before you start using your slab, wipe it clean of any dirt or smears with print cleaner or a similar solution. Then, when you are finished with the slab, use an ink spatula to remove the ink and wipe off any remaining ink with a cleaning solution and a rag. If you neglect these important cleaning steps, ink from past applications can affect your or other artists’ current work. Before using a new ink slab made of marble, use a rag to wipe the surface with linseed oil (#00 varnish), let the slab stand for a day, and then clean it with print cleaner. Treating the rock with oil before using it as an ink slab helps prevent ink color transfer. It is also a good idea to perform the same treatment on ink slabs that have not been used for long periods of time. If you accidentally scratch the surface of the rock with a spatula or other instrument, use a whetstone or sandpaper to smooth the area over and follow the treatment steps outlined above to repair the slab.
Ink slabs are available for purchase at general art supply stores and glass shops.