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Rocks » Petroglyphs, Pictographs and Rock Art
Rock Art: Petroglyphs and Pictographs |
Petroglyphs on sandstone at Newspaper Rock in southwestern Utah. Image by Jeremy Edwards © iStockphoto.com.
Petroglyphs, Pictographs and Rock Art |
Long before writing was developed, people recorded events and feelings through carvings and paintings on rocks. All of these markings are referred to as "Rock Art". Petroglyps and pictographs are different types of rock art.
What is a Petroglyph? |
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A petroglyph is an image that is carved into a rock. This "carving" can produce
a visible indentation in the rock as shown in the big horn sheep petroglyph above. This petroglyph is thought to have been carved by Native Americans into the wall of Buckskin Gulch in southern Utah, USA. (Image by Kevin Lange © iStockphoto.com.)
Petroglyphs have also been made by simply scraping away the weathered surface or desert varnish on the exterior of a rock. The petroglyphs on "Newspaper Rock", shown at the top of this page, were made by scraping away the thin black coating, known as "desert varnish" from the surface of the rock.
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What is a Pictograph? |
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A pictograph is a drawing or painting that is created on a rock. Because they are merely a surface coating, pictographs tend to be less durable than petroglyphs. The ones that survive are most often found in caves, rock shelters and areas with dry climates. The figures in the image above represent people of the Fremont Culture who used to live in what is now south-central Utah. (Image by Andrea Gingerich © iStockphoto.com.)
A variety of pigments have been used to make pictographs. Examples of these pigments include: charcoal from a campfire; blood from hunted or sacrificed animals; and mineral materials such as chalk, limonite or hematite.
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Who Are the Artists? |
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Petroglyphs are almost never attributed to a specific person. However they are often attributed to a specific group of people who inhabited or passed through the area where the petroglyph occurs. Shown in the image above is a rock with a large number of petroglyphs in Petrified Forest National Park, Arizona, USA. This rock is easy to see by anyone who passes by. The images on it could have been made by some of the early people to inhabit this area, they could have been made by people who passed through many hundreds of years later or they could have been made by recent vandals. (Image by Tom Marvin © iStockphoto.com.)
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Rock Art or Vandalism? |
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Carving or painting on rock to express yourself was great fun before the days of private land ownership, national forests, state parks and other private or government preserves. Today, if you paint the rocks in a national park or on another person's private land you will likely be guilty of vandalism. (Image by Richard Clark © iStockphoto.com.)
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Contributor: Hobart King
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