noun
definition
A low-grade, brownish-black coal
example
Lignite is the main natural resource of Thailand.
Examples of lignites in a Sentence
Krantzite, a soft amber-like resin, found in the lignites of Saxony.
It varies in colour from a light brown in the newest lignites to a pure black, often with a bluish or yellowish tint in the more compact anthracite of the older formations.
The maximum hardness is from 2.5 to 3 in anthracite and hard bituminous coals, but considerably less in lignites, which are nearly as soft as rotten wood.
Some lignites are, however, quite as brilliant as anthracite; cannel and jet may be turned in the lathe, and are susceptible of taking a brilliant polish.
The proportion of carbon in bituminous coals may vary from 80 to 90% the amount being highest as they approach the character of anthracite, and least in those which are nearest to lignites.
Lignites, as a rule, are generally found in strata of a newer geological age, but there are many instances of perfect coals being found in such strata.
It is generally largest in lignites, which may sometimes contain 30% or even more, while in the coals of the coal measures it does not usually exceed from 5 to io%.
In southern Otago the Oligocene beds are brown coals and lignites with oil shales, which, at Orepuki, contain 47% of oil and gas, with 8% of water.
The Eocene beds are nummulitic. There is a lacustrine group which has usually been placed in the Lower Eocene, but the discovery of Anthracotherium magnum in the interbedded lignites proves it to be Oligocene, in part at least.
The lignites of Hesse, Cassel, &c., are interstratified with basaltic lava-flows which form the greater part of the Vogelsbarg and other hills.
Ethylene succinic acid occurs in amber, in various resins and lignites, in fossilized wood, in many members of the natural orders of Papaveraceae and Compositae, in unripe grapes, urine and blood.
Volcanic activity may have extended into Miocene times; but the only fossiliferous relics of Cainozoic periods later than the Eocene are the pale clays and silicified lignites on the south shore of Lough Neagh, and the shelly gravels of pre-glacial age in county Wexford.
These also, like the lignites of Bovey Tracey, have been referred to the Miocene period, on the supposed evidence of the plants; but more recent discoveries by Gardner tend tb throw doubt on this allocation, and suggest that, though of various ages, the first-formed of these deposits may date back to early Eocene times.