Petroglyphs and Pictographs

Some of the oldest known rock art features are pictographs in France and Spain; cave paintings made by the Cro-Magnon culture of early humans have been dated to more than 30,000 years old. Protected from rain and sunlight in deep, underground passages, these features have withstood the ravages of time. Most of these colorful images are of animals such as deer and antelope, and are strikingly detailed and life-like.

When humans migrated into North America some 12,000 years ago, the practice of creating rock art was brought with them. As time progressed and people spread out across the Western Hemisphere so did the use of rock art. Eventually, nearly all of the more than 200 distinct Native American tribes in North America used some form of rock art in ceremony. Interestingly, many of the artistic elements or patterns used in petroglyphs and pictographs are very similar among these many diverse groups.

From historic cultures that continue to create rock art, we have learned that petroglyphs were made by using a hand-held stone as a chisel or hammer to etch designs into boulders.

Pictographs, however, were considerably more complex to make because of the materials required for paint. Red pigments, which generally comprise the most common color found in rock paintings, were made from ground iron oxides obtained from the minerals hematite or magnetite. Talc, gypsum, or lime was used to make white; charcoal or graphite were employed for black; and copper ores were sometimes used for greens and blues.

These minerals were ground into fine powders then mixed with a resin, such as pine pitch. An oil base was sometimes added by grinding certain seeds or extracted from animal fat. Paints were applied either by fingers or with brushes made from the shredded end of a stick, animal fur, or fibrous plant leaves.