Lamps were most often small slabs of limestone hollowed in the center to hold the fuel. Hundreds of these have been discovered from sites all over Europe. However, some of these lamps were very carefully prepared. Special kinds of stone obtained from distant regions were preferred. These special lamps, which seem especially prevalent in painted caves, were often decorated with abstract or animal forms. De Beaune was able to reconstruct Ice Age lamps and to measure the amount of light given off. She concluded that the amount of light produced in a dark place would have created the light conditions that we associate with dusk.