[bog-hed] 
| compact bituminous coal that burns brightly and yields large quantities of tar and oil upon distillation. |
boghead coal
mineral substance intermediate between oil shale and coal. Whereas destructive distillation of coals produces compounds of carbon and hydrogen with carbon atoms linked in six-membered rings, torbanite produces paraffinic and olefinic hydrocarbons (compounds with carbon linked in chains). As the hydrocarbon content of oil shale increases, torbanite becomes cannel coal. Torbanite occurs abundantly in France, New South Wales, South Africa, and the northeastern United States. It was named for its occurrence on Torbane Hill, Bathgate, West Lothian
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