Obsidian and Tonalite Definition

Definition of Obsidian and Tonalite

The general Obsidian and Tonalite definition can be stated as: 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. On the other hand, Tonalite is a coarse-grained plutonic rock consisting mainly of sodic plagioclase, quartz, and hornblende or other mafic minerals with phaneritic texture. Along with definition of Obsidian and Tonalite, get to know about Properties of Obsidian and Tonalite. Get to know more information about Obsidian and Tonalite origin and discoverer, etymology and class.

History of Obsidian and Tonalite

The history of Obsidian and Tonalite 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.

Obsidian and Tonalite Origin and Discoverer

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

Etymology of Obsidian and Tonalite

Along with Obsidian and Tonalite definition, know more about the etymology of Obsidian and Tonalite. Etymology of Obsidian and Tonalite gives information about origin and formation of a particular rock. Know more about Formation of Obsidian and Formation of Tonalite. The etymology of Obsidian is From Latin obsidianus, misprint of Obsianus (lapis) (stone) of Obsius while that of Tonalite is From Latin obsidianus, misprint of Obsianus (lapis) (stone) of Obsius. The process of formation of rocks defines the class of rock. All the rocks in a class are formed by similar processes. Obsidian and Tonalite belong to Igneous Rocks. The sub-class, group and other categories of Obsidian and Tonalite are listed below.

For Obsidian,

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

For Tonalite,

• Sub-class: Durable Rock and Hard Rock
• Group: Plutonic
• Other Categories: Coarse grained rock, Fine grained rock, Medium grained rock and Opaque rock