- Argillite
:"Argillite" may also refer to
Argillite, Kentucky ."An argillite (pronEng|ˈɑrdʒɨlaɪt) is a fine-grained
sedimentary rock composed predominantly of induratedclay particles. Argillites are basicallylithified muds and oozes. They contain variable amounts ofsilt -sized particles. The argillites grade intoshale when the fissile layering typical of shale is developed. Another name for poorly lithified argillites is "mudstone ". These rocks, although variable in composition, are typically high inaluminium andsilica with variablealkali andalkaline earth cation s. The term "pelitic" or "pelite" is often applied to thesesediment s and rocks.Metamorphism of argillites producesslate ,phyllite , and peliticschist .The Haida carvings of
Queen Charlotte Islands along the coast ofBritish Columbia are notable aboriginal art treasures created from a type of a hard, fine black silt argillite, sometimes called "blackslate ", which occurs only at a quarry on aSlatechuck Mountain in the upper basin ofSlatechuck Creek , near the town of Skidegate onGraham Island ("chuck" is theChinook Jargon term for water, and can mean a creek or lake). While at one time, around 1900, it was shipped to Victoria for manufacturing, today theHaida have a monopoly on use of the argillite. This artwork has been of high quality and prized around the world since the Haida first began carving it to sell to sailors around 1800, and modern Haida carvers continue the tradition today, with stunning design and skill.References
* [http://www.cst.cmich.edu/users/dietr1rv/argillite.htm R. V. Dietrich, 2005, "Gemrocks: Argillite"] Accessed Dec. 22, 2005.
* [http://www.civilization.ca/tresors/treasure/270eng.html Museum of Civilization Haida argillite gallery]
* [http://minfile.gov.bc.ca/Summary.aspx?minfilno=103F%20%20018 BC Govt MINFILE report] , includes history and geological data.
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