1 Definition
1.1 Definition
Schist is a medium grade metamorphic rock with medium to large, flat, sheet like grains in a preferred orientation
Tephrite is an aphanitic to porphyritic textured, volcanic igneous rock
1.2 History
1.2.1 Origin
1.2.2 Discoverer
1.3 Etymology
From French schiste, Greek skhistos i.e. split
From Greek tephra, ashes from Indo-European base, to burn
1.4 Class
Metamorphic Rocks
Igneous Rocks
1.4.1 Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Hard Rock
1.5 Family
1.5.1 Group
1.6 Other Categories
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock