Lignite and Obsidian Definition

Definition of Lignite and Obsidian

The general Lignite and Obsidian definition can be stated as: Lignite is a soft brownish coal which shows traces of plants and is intermediate between bituminous coal and peat. On the other hand, Obsidian is a naturally occurring volcanic glass formed as an extrusive igneous rock. It is produced when felsic lava extruded from a volcano cools rapidly with minimum crystal growth. Along with definition of Lignite and Obsidian, get to know about Properties of Lignite and Obsidian. Get to know more information about Lignite and Obsidian origin and discoverer, etymology and class.

History of Lignite and Obsidian

The history of Lignite and Obsidian gives information about where the rock was found and who was its discoverer. Almost each and every aspect of Earth's history is recorded in rocks be it the volcanoes which were erupted or the plants, animals and organisms which are now extinct, as rocks are present from millions of years.

Lignite and Obsidian Origin and Discoverer

Lignite and Obsidian definition gives us a brief idea about the two rocks. In some cases, the definition also gives summary about the Formation of Lignite and Obsidian. In this section, you will know about Lignite and Obsidian Origin and Discoverer. Origin of Lignite is France whereas Origin of Obsidian is Ethiopia. It is interesting to know the name of Lignite and Obsidian discoverer. The Discoverer of Lignite is Unknown and the discoverer of Obsidian is Obsius.

Etymology of Lignite and Obsidian

Along with Lignite and Obsidian definition, know more about the etymology of Lignite and Obsidian. Etymology of Lignite and Obsidian gives information about origin and formation of a particular rock. Know more about Formation of Lignite and Formation of Obsidian. The etymology of Lignite is From French, Latin lignum wood + -ite1 while that of Obsidian is From French, Latin lignum wood + -ite1. The process of formation of rocks defines the class of rock. All the rocks in a class are formed by similar processes. Lignite belongs to Sedimentary Rocks while Obsidian belongs to Igneous Rocks. The sub-class, group and other categories of Lignite and Obsidian are listed below.

For Lignite,

• Sub-class: Durable Rock and Soft Rock
• Group: Not applicable
• Other Categories: Coarse grained rock, Fine grained rock, Medium grained rock and Opaque rock

For Obsidian,

• Sub-class: Durable Rock and Medium Hardness Rock
• Group: Volcanic
• Other Categories: Opaque rock