Porphyry and Gneiss Definition

Definition of Porphyry and Gneiss

The general Porphyry and Gneiss definition can be stated as: Porphyry is a reddish-brown to purple igneous rock containing large phenocrysts of various minerals embedded in a fine-grained matrix. On the other hand, Gneiss is a common and widely distributed type of rock formed by high-grade regional metamorphic processes from pre-existing formations that were originally either igneous or sedimentary rocks. Along with definition of Porphyry and Gneiss, get to know about Properties of Porphyry and Gneiss. Get to know more information about Porphyry and Gneiss origin and discoverer, etymology and class.

History of Porphyry and Gneiss

The history of Porphyry and Gneiss 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.

Porphyry and Gneiss Origin and Discoverer

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

Etymology of Porphyry and Gneiss

Along with Porphyry and Gneiss definition, know more about the etymology of Porphyry and Gneiss. Etymology of Porphyry and Gneiss gives information about origin and formation of a particular rock. Know more about Formation of Porphyry and Formation of Gneiss. The etymology of Porphyry is From Old French porfire, from Italian porfiro and in some cases directly from Latin porphyrites while that of Gneiss is From Old French porfire, from Italian porfiro and in some cases directly from Latin porphyrites. The process of formation of rocks defines the class of rock. All the rocks in a class are formed by similar processes. Porphyry belongs to Igneous Rocks while Gneiss belongs to Metamorphic Rocks. The sub-class, group and other categories of Porphyry and Gneiss are listed below.

For Porphyry,

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

For Gneiss,

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