Definition
Greywacke is defined as a dark coarse-grained sandstone rock which contains more than 15 per cent clay
Gabbro is an intrusive igneous rock which is chemically equivalent to plutonic Basalt
History
Origin
-
Germany
Discoverer
Unknown
Christian Leopold von Buch
Etymology
From German Grauwacke, from grau grey + wacke
From Latin glaber bare, smooth, bald
Class
Sedimentary Rocks
Igneous Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Hard Rock
Family
Group
-
Plutonic
Other Categories
Fine Grained Rock, Opaque Rock
Coarse Grained Rock, Opaque Rock