Definition
Granulite is fine to medium grained metamorphic rock with a granular of polygonal crystals.
Tachylite is a vitreous form of basaltic volcanic glass. This glass is formed naturally by the rapid cooling of molten basalt
History
Origin
Central Europe
Iceland
Discoverer
Unknown
Unknown
Etymology
From Latin granulum, a little grain or fine grained
From German Tachylite, from tachy- + Greek lutos soluble, melting
Class
Metamorphic Rocks
Igneous Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Medium Hardness Rock
Family
Group
-
Volcanic
Other Categories
Coarse Grained Rock, Medium Grained Rock, Opaque Rock
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock