Definition
Gritstone or grit is a hard, coarse-grained, siliceous sandstone
Larvikite is an igneous rock and a variety of monzonite, notable for the presence of thumbnail-sized crystals of feldspar
History
Origin
Pennines, England
Larvik, Norway
Discoverer
J.J. Ferber
Unknown
Etymology
From Grit + Stone
From the town of Larvik in Norway, where this type of igneous rock is found
Class
Sedimentary Rocks
Igneous Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Hard Rock
Family
Group
-
Plutonic
Other Categories
Coarse Grained Rock, Opaque Rock
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock