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,
Chalk outline fairy" is occasionally used to describe an officer that makes the chalk outline, often without authorization and while unwittingly contaminating the scene. While the use of chalk is uncommon, investigators may make smaller marks, or use removable flags, index cards, or even markers, to indicate important positions, particularly if other references are not available. Chalk outlines of bodies are familiar tropes in popular culture. Often they are used in humorous ways depicting awkward positioning or meticulous precision, or portending a character's impending death by having them prematurely fall into a drawn outline. "The Naked Gun" series made extensive use of