Paint Pigment Basics

By Jim Hingst @hingst_jim 

Photography of Lascaux animal painting*.
Paintings of bulls, deer and horses were
painted using basic earth pigments about
17,000 years ago in southwestern France.

People have described pigments as powdered rock or dirt. In some cases this is true. Many of the first pigments that men (in some cases, cavemen) used were comprised of clays or ground up rocks. These pigments have been used for painting for tens of thousands of years. These earth colors include Siennas, Umbers and Ochres.

In large part, the coloration of the pigment is determined by the type of iron oxide (in other words, rust) that it contains. The color of these pigments can be altered by roasting the raw pigment with an absence of oxygen. This process, known as calcination, alters the molecular structure and appearance of the pigment.  

The wide range of these oxides provides an array of colors from yellows, reds, browns and blacks.   Originally, these colors were dug straight out of the earth. Today, most of these earth colors are synthetic. Whether the pigment is synthetic or natural, the earth colors are very durable, relatively opaque and chemically resistant. Many of the old masters of the Renaissance used these earth tones for their paintings because of the warm and natural tones they produced, in addition to being readily available and inexpensive.

Semiprecious stones were also ground up to make pigment powders. Perhaps the most prized stone was lapis lazuli, which was comprised of the ultramarine lazurite and various impurities. This stone was only mined in a remote part of northeastern Afghanistan. Traders transported the lapis lazuli for more than 3000 miles where it was sold to the merchants in Venice, where it was more valued more highly than gold. 

Because lapis lazuli was so rare and so difficult to process in removing impurities, the price was prohibitive. For this reason, some Renaissance artists used less costly blue pigments, such as azurite or smalt (blue ground glass). Another way to reduce the cost of painting an object with the ultramarine lazurite (the blue component of lapis lazuli) pigment  was to first paint it with a less expensive blue and then overpaint it with an ultramarine blue glaze.

Other pigments were byproducts of ceramics, glass making and smelting. These pigments resulted from chemicals being fired at extremely high temperatures. Many of these compounds contain heavy metals and high toxic substances.

While we may associate synthetic pigments with the colorants, which German and French chemists develop in the last 300 years, the first synthetic colors were created more than 5000 years ago by the Egyptians. The most notable of these synthetic colors was Egyptian Blue.

Synthetic colorants were also created through the trial and error experimentation of alchemists in the Medieval and Renaissance periods. The first modern synthetic pigment was developed in 1704 by a German chemist. This scientist was attempting to manufacture a red pigment. By accident, he created what became to be known as Prussian Blue.

Experimentation in creating synthetic pigments accelerated, when the French government offer prize money to the first person to develop a synthetic Ultramarine Blue pigment, which would be a cost-effective alternative to lapis lazuli. 

Today sign makers and artists have many more colors from which to choose because of the advances attained from the Industrial Revolution through the achievements of modern chemistry in the 20^th century. Everything a painter needs is prepackaged in a tube or a can. Much of what is lost among artists and artisans is the knowledge and craft of making paint.

* Photography of Lascaux animal painting by Prof saxx.  The author permits further using of the picture for private, public or commercial purposes.

About Jim Hingst: After fourteen years as Business Development Manager at RTape, Jim Hingst retired. He was involved in many facets of the company’s business, including marketing, sales, product development and technical service.

Hingst began his career 42 years ago in the graphic arts field creating and producing advertising and promotional materials for a large test equipment manufacturer.  Working for offset printers, large format screen printers, vinyl film manufacturers, and application tape companies, his experience included estimating, production planning, purchasing and production art, as well as sales and marketing. In his capacity as a salesman, Hingst was recognized with numerous sales achievement awards.

Drawing on his experience in production and as graphics installation subcontractor, Hingst provided the industry with practical advice, publishing more than 150 articles for  publications, such as  Signs Canada, SignCraft,  Signs of the Times, Screen Printing, Sign and Digital Graphics and  Sign Builder Illustrated. He also posted more than 450 stories on his blog (hingstssignpost.blogspot.com). In 2007 Hingst’s book, Vinyl Sign Techniques, was published.  Vinyl Sign Techniques is available at sign supply distributors and at Amazon. 

Slides of Jim's Artwork

© 2017 Jim Hingst