- Fine-grained, dense sedimentary rock consisting of interlocking crystals of quartz approximately 30 microns in diameter. Chert and its varieties, such as flint, are non-gem varieties of cryptocrystalline-granular quartz. These stones chip very easily and thus may be fashioned into tools with a sharp edge; they are also used for building.
- Thin, flat, circular objects of any material.
- Prehistoric hammering implements consisting of rounded stones.
- Typically reserved to refer narrowly to the cultures of the native peoples of the United States and Canada, excluding the Eskimos and Aleuts. For the indigenous peoples of Canada use the term "First Nations." For the broader concept of the cultures of any native peoples of Central America, South America, North America, or the West Indies who are considered to belong to the Mongoloid division of the human species, use "Amerindian (culture)."
- Broad, flat objects, usually made of lightweight wood or heavy paper over a firm support, used by painters for laying out and mixing colors.
- A very fine-grained, foliated, non-layered metamorphic rock, generally produced by metamorphism of shale under relatively low pressure and temperature. It occurs in many varieties, including clay, hornblende, mica, talc slate, and others, all of which have the common property of splitting readily into thin plates.
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