Cobalt green was discovered in 1780 by Sven Rinmann and introduced to artists in the early 19th century. It was valued by the Impressionists for its luminosity and relative transparency compared to other opaque greens available at the time. Like cobalt blue, it carries a characteristic clarity that synthetic organic greens lack.

Clear, luminous, and mineral. Cobalt green has a freshness and transparency that distinguishes it from earthier greens. It is the green of sunlight on water, of spring leaves against a bright sky. Associated with clarity, openness, and the particular quality of light in Impressionist painting.

Cobalt green is a relatively specialist artist colour — less universally used than phthalo or viridian, but prized by watercolourists and landscape painters for its specific luminous quality. The cobalt pigment family (cobalt blue, cobalt violet, cobalt green, cobalt turquoise) represents a remarkable range of colours sharing the same metal, each with distinctive optical properties.