Paint is composed of two key elements: pigment and binder.
Pigments begin in powder form and are often ground up part of naturally occurring elements including rocks, plants, flowers, dirt, and minerals. The rarity of the pigment is what causes price fluctuation in paints. Pigments like cadmium and cobalt are very expensive, for example are very expensive so colors like "cadmium red" will cost more per tube. Centuries ago, artists would write clauses about pigments into their contracts, so that the charges for say high-grade lapis lazuli would be determined before the painting began. The wealthy often asked to be painted against a blue background or in blue clothing, showing off their wealth through the copius use of lapis lazuli. It is believed that this is also why we see the Virgin Mary wearing the blue robes she has become synonymous with; artists wanted such a holy figure to be painted with only the finest pigments.
But enough about that, the second part of paint is the binder, or the goo that holds the powdered pigment. Many binders are synthetic (like latex or acrylic) but they can also be natural (linseed or walnut oil for example, or egg in tempera paint). The binder determines what kind of clean up will be associated with the paint. Acrylic and laytex binders are water soluble, while oil requires a solvent like mineral spirits, OMS, or d-limonene.
Many artists mix their own paint by combining certain amounts of binder and pigment. From there, you can add many mediums and solvents so control the viscosity, texture, and behavior of your paint.
Rose
www.rosebriccetti.com
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