Definition
An iron rich extrusive rock found as a member of the alkali basalt magma series
Greywacke is defined as a dark coarse-grained sandstone rock which contains more than 15 per cent clay
History
Origin
Isle of Mull, Scotland
-
Discoverer
Ben More
Unknown
Etymology
From the name of discoverer, Ben More
From German Grauwacke, from grau grey + wacke
Class
Igneous Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Hard Rock
Family
Group
Volcanic
-
Other Categories
Fine Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock