出典:Wiktionary
出典:Wikipedia
出典:『Wikipedia』 (2010/05/27 15:58 UTC 版)
Gilsonite is the registered trademark for a form of natural asphalt found only in the Uintah Basin of Utah; the non-trademarked mineral name is uintaite or uintahite. 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.