Peach black is a grey-black pigment

Pigment

A pigment is a material that changes the color of reflected or transmitted light as the result of wavelength-selective absorption. This physical process differs from fluorescence, phosphorescence, and other forms of luminescence, in which a material emits light.Many materials selectively absorb...

 originally obtained from burnt peach stones. Other early formulations included aniline black and soot

Soot

Soot is a general term that refers to impure carbon particles resulting from the incomplete combustion of a hydrocarbon. It is more properly restricted to the product of the gas-phase combustion process but is commonly extended to include the residual pyrolyzed fuel particles such as cenospheres,...

from burnt petroleum or wax. Current formulations contain zinc oxide instead. According to some sources, the pigment has a tendency to green, making it useful for darkening foliage and ground cover.