Up to 1870 there was more anthracite mined in Pennsylvania than bituminous in the whole country, but since that year the production of the latter has become vastly the greater, the totals in 1907, in which year each stood at its maximum, being 83,268,754 and 332,573,944 tons respectively.
The mineral wealth of Ohio consists largely of bituminous coal and petroleum, but the state also ranks high in the production of natural gas, sandstone, limestone, grindstone, lime and gypsum.
Coal, chiefly bituminous, occurs in large quantities in Nova Scotia, British Columbia and in various parts of the north-west (lignite), though most of the anthracite is imported from the United States, as is the greater part of the bituminous coal used in Ontario.
Geologically the anthracite and bituminous coals mainly belong to the same formation, the Carboniferous, and this is especially true of the better qualities; though it is stated by the United States Geological Survey that the geQlogic age of the coal beds ranges from Carboniferous in the Appalachian and Mississippi Valley provinces to Miocene (Tertiary) on the Pacific coast, and that the quality of the coal varies only to a very uncertain degree with the geologic age.
Anthracite is mined in the St Lucia Bay district, and bituminous coal is found in the Nqutu and Kyudeni hills.
The production of bituminous coal has also increased very rapidly.
It is also found among the distillation products of bituminous coal, lignite, and various shales, and has been detected in fusel oil and crude petroleum.
The thin seams of the Calciferous Sandstone are not workable, but the bituminous shales in the Firth of Forth basin are largely worked for the manufacture of mineral oil.
It possesses unlimited supplies, as yet not greatly exploited, of fine building stones, some oil and asphalt, and related bituminous products, a few precious and semi-precious stones (especially tourmalines, beryls and aquamarines found near Canyon near the Royal Gorge of the Arkansas river), rare opalized and jasperized wood (in the eastern part of the El Paso county), considerable wealth of lead and copper, enormous fields of bituminous coal, and enormous wealth of the precious metals.
In the east portion of the state are immense beds of bituminous coal, often at shallow depths or cropping out on the surface.