Definition
Foidolite is a rare type of coarse-grained intrusive igneous rock with a feldspathoid mineral content greater than 60%
Phonolite is an uncommon extrusive igneous rock volcanic rock of intermediate chemical composition between felsic and mafic
History
Origin
-
-
Discoverer
Unknown
Unknown
Etymology
From the mineral feldspathoid which is the main content of rock
From the Greek meaning sounding stone because of the metallic sound it produces if an unfractured plate is hit
Class
Igneous Rocks
Igneous Rocks
Sub-Class
Durable Rock, Soft Rock
Durable Rock, Medium Hardness Rock
Family
Group
Plutonic
-
Other Categories
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock