Davy's grey was developed by Henry Davy in the 19th century and adopted by watercolourists for its particular granulating quality — the mica and other minerals in ground slate produce a characteristic texture when used in wet watercolour techniques. This granulation gives skies and water passages an organic, stone-like quality.

Natural, granulating, and atmospheric. Davy's grey has a quality that synthetic greys lack — its mineral origin gives it a slightly rough, granulating character in watercolour that mimics natural stone and atmospheric haze. Associated with northern European landscapes, overcast skies, and the particular quality of light on grey days.

Davy's grey is valued by watercolourists specifically for its granulating behaviour — the mineral particles in the pigment settle unevenly in wet washes, creating organic textures that flat synthetic greys cannot reproduce. This makes it particularly useful for painting stone, weathered surfaces, and atmospheric sky conditions. It is one of the few artist pigments that is literally made from the landscape it is often used to depict.