Lithographic artists used grease crayons to sketch images on a block of limestone.
From the voanews.com
I did a quick sketch of the block house and put in some color notes.
From the theepochtimes.com
Once you are satisfied with your design, sketch it directly onto the linoleum block.
From the denverpost.com
Wynn and her colleagues studied the reactions of infants to a sketch in which a brightly coloured wooden block with goggly eyes attempts to climb up a hill.