Chalk produce, and thus widely used in the developing world, calcium-based chalk can be made where the crumbling particles are larger and thus produce less dust, and is marketed as "dustless chalk". Colored chalks, pastel chalks, and sidewalk chalk (shaped into larger sticks and often colored), used to draw on sidewalks, streets, and driveways, are primarily made of gypsum. Chalk is a source of quicklime by thermal decomposition, or slaked lime following quenching of quicklime with water. In southeast England, deneholes are a notable example of ancient chalk pits. Such bell pits may also mark the sites of ancient flint mines,
Pick-up sticks (Haida) Pick-up sticks (Haida) Haida pick-up sticks exist in two sorts. There were non-decorated thin playing sticks (not collected) and the other decorated, containing three sets of sticks. These were named after animals or birds only known by the owner or his family, according to Charles F. Newcombe. The decoration consists of rings and spiral markings for distinction. Most elaborated sets may contain a Haida art gallery of more than fifty drawings. Made of maple wood, they are decorated with pyro-engravings or carvings. Many pyro-engravings are inlaid with copper or abalone shell. The drawings are complex and an artistic challenge as