Definition
Felsite is a very fine grained volcanic rock that may or may not contain larger crystals and light colored rock that typically requires petrographic examination or chemical analysis for more precise 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
History
Origin
-
USA
Discoverer
Unknown
Bayley
Etymology
From English feldspar and -ite
From its occurrence at Litchfield, Maine, USA
Class
Igneous Rocks
Igneous Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Medium Hardness Rock
Family
Group
Volcanic
Plutonic
Other Categories
Fine Grained Rock, Opaque Rock
Coarse Grained Rock, Opaque Rock