Definition
Greywacke is defined as a dark coarse-grained sandstone rock which contains more than 15 per cent clay
Breccia is a rock consisting of angular fragments of stones which are cemented by finer calcareous material
History
Origin
-
England
Discoverer
Unknown
Unknown
Etymology
From German Grauwacke, from grau grey + wacke
From Italian, literally gravel, Germanic origin and related to break
Class
Sedimentary Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Hard Rock
Family
Group
-
-
Other Categories
Fine Grained Rock, Opaque Rock
Coarse Grained Rock, Medium Grained Rock, Opaque Rock