Charbonnel Powdered Bitumen, or Asphaltum is a general studio material used in etching and lithography. It is an ingredient used in the formulation of grounds and resists for etching. It can also be used as a powder for creating aquatints, in contrast to rosin it is soluble in turpentine and white spirit as opposed to alcohol. In the lithography studio, it is used as part of the image processing on plate and stone, reinforcing the greasy elements of the lithographic drawing.
Charbonnel Powdered Bitumin can also be used as a brownish-black colouring pigment.