Pigments

A wide array of Pigments are used in paints and plastics, and sometimes mortar. This article will just introduce some of the readily available low cost pigments useful for DIY colouring and experimentation.

Iron Oxide

Dull red
Can make mixes pink, red or brown
One of the most stable pigments known, iron oxide keeps its colour for centuries
Red brick dust may be used as a substitute

Lamp Black

Soot
Black
Can contain hygroscopic salts, so not good for indoor use

Subsoil

Various browns
Can make mixes anything from broken white to dark brown

Lime

White or broken white, depending on purity
Mixes can produces white, cream, broken white or grey

Topsoil

Brown
Added to cement it promotes organic growth on the cement, making it look weathered & natural
Likely to turn green if it stays wet

Stone Waste

Various colours
Mix with cement to produce a more stone-like appearance

Coal Ash

Black
Incorporated into lime mortar to make black mortar
Black mortar is sometimes prone to premature failure, so its use is best kept to being a minority of the mortar used.

Laundry blue

Gives a pale sky blue colour
If used in lime based paints it can fade in time

Commercial Mortar Pigments

Tins of pigment are available from BMs at small cost, but most colours are prone to streaking and bleaching during the life of the mortar. Red pigment however is iron oxide, and is very stable.