Definition
Marble is a non-foliated metamorphic rock which is composed of recrystallized carbonate which is formed when limestone is exposed to high temperatures and pressures over a long time
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
History
Origin
Egypt
Ethiopia
Discoverer
Unknown
Obsius
Etymology
From the Greek marmaros, shining stone and also from the English word marmoreal meaning marble-like
From Latin obsidianus, misprint of Obsianus (lapis) (stone) of Obsius
Class
Metamorphic Rocks
Igneous Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Medium Hardness Rock
Family
Group
-
Volcanic
Other Categories
Medium Grained Rock, Opaque Rock
Opaque Rock