This was a large 8ft x 3ft 'drawing' I made when a few of the students on the Sheffield Hallam part-time Fine Art course hired a big shed out on the western edge of the Pennines for a weekend of arty fun. It is largely made with natural pigments (aka mud) applied initially with a yard broom, and charcoal.
It only exists as a scan of a 5x3inch photograph unfortunately (or not). And a small dry-point print. And a linked drawing.
See also Books for use of natural pigments