Sanguine is chalk

Chalk

Chalk is a soft, white, porous sedimentary rock, a form of limestone composed of the mineral calcite. Calcite is calcium carbonate or CaCO3. It forms under reasonably deep marine conditions from the gradual accumulation of minute calcite plates shed from micro-organisms called coccolithophores....

 of a reddish color, often called the true colour of blood. tending to brown, used in drawing

Drawing

Drawing is a form of visual art that makes use of any number of drawing instruments to mark a two-dimensional medium. Common instruments include graphite pencils, pen and ink, inked brushes, wax color pencils, crayons, charcoal, chalk, pastels, markers, styluses, and various metals .An artist who...

, The word also describes any drawing done in sanguine.

Technique

Sanguine (icon) lends itself naturally to sketches, life drawings, and rustic scenes. It is ideal for rendering modeling and volume. In the form of wood-cased pencils and manufactured sticks, sanguine may be used similarly to charcoal and pastel. As with pastel, a mid-toned paper may be put to good use. A fixative often is applied to preserve the finished state of the drawing.