Petroleum and natural gas also occur in the plateau rocks in great quantities.
- The state's great mineral wealth is in coals of various kinds, petroleum, and natural gas.
Petroleum was collected for use in the most remote ages of which we have any records.
The earliest mention 'of American petroleum occurs in Sir Walter Raleigh's account of the Trinidad pitch-lake in 1595; whilst thirty-seven years later, the account of a visit of a Franciscan, Joseph de la Roche d'Allion, to the oil springs of New York was published in Sagard's Histoire du Canada.
Deposits of copper, tin, iron and tungsten have been discovered, and a variety of other mineral products (graphite, mica, spodumene, coal, petroleum, &c.).