Definition
Greywacke is defined as a dark coarse-grained sandstone rock which contains more than 15 per cent clay
Hornblendite is a type of igneous plutonic rock consisting mainly of amphibole hornblende and is a type of Amphibolite rock
History
Origin
-
-
Discoverer
Unknown
Unknown
Etymology
From German Grauwacke, from grau grey + wacke
From German, Horn horn + blende
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, Medium Grained Rock, Opaque Rock