Definition
Lignite is a soft brownish coal which shows traces of plants and is intermediate between bituminous coal and peat
Travertine is a mineral consisting of layered calcium carbonate formed by deposition from spring waters
History
Origin
France
Italy
Discoverer
Unknown
Marcus Vitruvius Pollio
Etymology
From French, Latin lignum wood + -ite1
From Italian travertino a kind of building stone, from Tiburs, adjective from Tibur (Tivoli), in Italy
Class
Sedimentary Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Soft Rock
Durable Rock, Medium Hardness Rock
Family
Group
-
-
Other Categories
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock