Waco Gem and Mineral Club, Waco, Tx

14.4 Making Rock Art

 

14.4: Making Rock Art

a) Cave painting. Near my home in southern California are cave paintings, or pictographs, left by Chumash Indians. The primary colors are red from hematite, black from charcoal or burnt manganese, and white from clay or diatomaceous earth. Indians ground such materials with mortars and pestles, then mixed the resulting powdery pigments with a binder (water, grease from animal fat, or oil from crushed seeds). Paint brushes were crafted from feathers, coarse hair or fur, or vegetable fibers bound together or inserted into cane tubes. Paint also was applied simply by finger. Work with your kids to make paint and use it to decorate large, flat rocks. Here are some minerals that have been crushed, mixed with oils or animal fats, and used in paints over the ages (as an alternative to oils or animal fats, you can use white glue diluted in water as your binder):

  • Green Clay
  • White Chalk
  • Yellow Clay
  • White Gypsum
  • Yellow Limonite
  • Black Charcoal
  • Brown Clay
  • Blue Azurite
  • Red Clay
  • Green Malachite
  • White Clay
  • An Earthy Variety of Red Hematite

WARNING!! In some books, you may read that yellow and red paint pigments can be ground from orpiment and realgar. While this is true, both are sulphides of arsenic and can be dangerous and even toxic. Don’t use these with your club’s kids!

b) Petroglyphs. Petroglyphs are images that have been chipped into stone and are often seen at cliff sites or covering large boulders in the American Southwest. In deserts, rocks often get coated with a dark crust called desert varnish. Native Americans chipped though this coating to create their petroglyph artworks, sometimes creating huge murals stretching across a cliff face. To help kids make their own petroglyphs, provide soft, flat rocks such as slabs of shale or sandstone. (If you don‘t have a source readily available that you can collect from the field, try a building supply store for flagstones. See if they have any broken ones they may be willing to donate for free.) You also can make a soft, flat surface with plaster. Lightly coat the surface of your rock or plaster slab with a red-brown or black paint to simulate desert varnish. Then give kids small, pointed rocks to chip images into the desert varnish.

c) Sand painting. The Navajo, Tibetan monks, and Australian Aborigines are just some cultures that craft intricate patterns using colored sands. These are not usually meant to be permanent artworks but instead living, flowing works, just as sand blows across the landscape in the wind. Your kids could make similar, temporary works by drizzling sand in desired patterns onto a sidewalk or a sheet of cardboard. Or, for a permanent work of sand painting, you can give them sheets of cardboard or plywood and have them make patterns with white glue over which they sprinkle sands of different colors. If you have a nearby source from gullies, beaches, or river beds, you can use natural sands, or you can purchase a variety of vividly colored sands from aquarium supply stores.