Pictured are a couple of fat lamps I use. The one on the right was pecked from a limestone slab, the other is chiseled from soapstone. I always save the fat from scraping deer hides as fuel, but animal grease or vegetable oil would work. The wicks were simply cattail down rolled into a wick and wetted. Fat lamps were traced back to Ice Age Europe nearly 40,000 years ago and coincided with several other developments - art, personal adornments, and the dart & atlatl. This controlled use of fire allowed activities after sunset and in places naturally dark. These lamps are considered "closed curcuit" bowl lamps, in that they have a depression to catch and retain the fuel as it melts. This is the most common type found in all regions, in all periods, where fat lamps were used, and range from crude to elaborately carved. It is easy to let the mind wander in the evenings in camp, and picture animal skin clad men dabbing mineral pigments onto cave walls, in the flickering illumination of the lamp light.