1 Definition
1.1 Definition
Litchfieldite is a rare igneous rock which is coarse-grained, foliated and a variety of nepheline syenite, sometimes also called as nepheline syenite gneiss or gneissic nepeheline syenite
Greywacke is defined as a dark coarse-grained sandstone rock which contains more than 15 per cent clay
1.2 History
1.2.1 Origin
1.2.2 Discoverer
1.3 Etymology
From its occurrence at Litchfield, Maine, USA
From German Grauwacke, from grau grey + wacke
1.4 Class
Igneous Rocks
Sedimentary Rocks
1.4.1 Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Hard Rock
1.5 Family
1.5.1 Group
1.6 Other Categories
Coarse Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock