Gilsonite
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Gilsonite® since 1921 is the federally registered trademark of the American Gilsonite Company for a form of natural asphalt found in large amounts only in the Uintah Basin of Utah; the non-trademarked mineral name is uintahite or uintaite. It is mined in underground shafts and resembles shiny black obsidian. Discovered in the 1860s, it was first marketed as a lacquer, electrical insulator and waterproofing compound about twenty-five years later by Samuel H. Gilson. This unique mineral is used in more than 160 products, primarily in dark-colored printing inks and paints, oil well drilling muds and cements, asphalt modifiers, foundry sands additives and a wide variety of chemical products.
Modern geologists believe that the origin of uintaite is linked to the rich oil shale of the Green River Formation that underlies much of the basin. Deep vertical fissures in the earth's surface were once filled with a heavy, viscous hydrocarbon that lost its volatile constituents and solidified millions of years ago.
Uintaite is a glossy, black, solid hydrocarbon resin similar in appearance to coal or hard asphalt. It is brittle and lightweight and can be easily crushed into powder. Its unique chemical properties identify it as belonging to its own sub-group of the asphaltite family. Uintaite occurs naturally in a very pure state, and softens in a range of temperatures according to grade, from 300 to 400 degrees Fahrenheit (150-205 degrees Celsius). It has low specific gravity, high nitrogen content and very lower sulfur content. It is non-carcinogenic and safe to handle in its natural state.
Mining uintaite during World War II was by hand, using a six pound pick and then shoveling the ore into 200 pound sacks, which were sewn by hand. Some claim that in 1949 at the Pariette (Culmer) Gilsonite mine near Myton, Utah, Reed Smoot McConkie set the world record for ore mined by hand. Using his pick and shovel, he mined 175 bags of ore in an 8 hour day, 950 bags in a six day week, 1925 bags in a month and 15,000 bags in one year.
Recently, some Iranians maintain that there are some mines in Kermanshah, Iran that have been discovered and extracted for some years. However, the materials found in Iran are not uintaite and are chemically different in several important ways. The minerals found in Iran are a different asphaltite from the uintaite mineral found in Utah.
Gilsonite-brand uintaite's earliest applications included paints for buggies and emulsions for beer-vat lining. "Gilsonite" was used by Ford Motor Company as a principial component of the Japan Black lacquer used on most of the Ford Model T cars.
