Paint pigments come from natural soils and man made materials. Artists grind the substances into a fine powder.
Since powder can not adhere to the canvas, paint makers mix the powder in acrylic medium with a binder that enables the color to hold fast. The powder disperses in the gel as very fine dust.
Throughout history, artists have painted with ocher pigments in earthen yellow, brown and red. Golden colors are made from natural iron, clay, manganese and other minerals from the earth.
Earthen soils make up the natural browns, tans and violets.
Modern paint makers heat iron or clay to make the civil reds, yellows, blues and greens. These oxides are not as powerful as ochre and natural color, yet are bright.