Definition
Rapakivi Granite is a hornblende-biotite Granite containing large rounded crystals of orthoclase which are mantled with oligoclase
Tephrite is an aphanitic to porphyritic textured, volcanic igneous rock
History
Origin
Finland, Europe
Germany
Discoverer
Jakob Sederholm
Van Tooren
Etymology
From Finnish Rapakivi which stands for crumbly rock
From Greek tephra, ashes from Indo-European base, to burn
Class
Igneous Rocks
Igneous Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Hard Rock
Family
Group
Plutonic
Volcanic
Other Categories
Coarse Grained Rock, Opaque Rock
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock