Definition
Phonolite is an uncommon extrusive igneous rock volcanic rock of intermediate chemical composition between felsic and mafic
Arkose is a sedimentary rock, specifically a type of sandstone containing at least 25% feldspar
History
Origin
-
France
Discoverer
Unknown
Alexandre Brongniart
Etymology
From the Greek meaning sounding stone because of the metallic sound it produces if an unfractured plate is hit
From Auvergne region of France used by a French geologist Alexandre Brongniart in 1826 who applied this term to some feldspathic sandstones
Class
Igneous Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Hard Rock
Family
Group
-
-
Other Categories
Fine Grained Rock, Opaque Rock
Coarse Grained Rock, Opaque Rock