Definition
Greywacke is defined as a dark coarse-grained sandstone rock which contains more than 15 per cent clay
Kenyte is a variety of porphyritic phonolite or trachyte rock with rhomb shaped phenocrysts of anorthoclase with variable olivine and augite in a glassy matrix
History
Origin
-
Mount Kenya
Discoverer
Unknown
J. W. Gregory
Etymology
From German Grauwacke, from grau grey + wacke
From the mountain ranges- Mount Kenya and is named by J. W. Gregory in 1900
Class
Sedimentary Rocks
Igneous Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Medium Hardness Rock
Family
Group
-
-
Other Categories
Fine Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock