from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. A dark, vitreous mineraloid produced by surface oxidation of lignite
Sorry, no etymologies found.
"Lignite, also known as leonardite, mined lignin, brown coal, and slack, is an important constituent to the oil well, drilling industry.
Lignite, or leonardite as it will be referred as hereafter, is technically known as a low rank coal between peat and sub-bituminous.