1 Definition
1.1 Definition
Tephrite is an aphanitic to porphyritic textured, volcanic igneous rock
Slate is a fine-grained, foliated, homogeneous metamorphic rock derived from an original shale-type sedimentary rock composed of clay or volcanic ash through low-grade regional metamorphism
1.2 History
1.2.1 Origin
1.2.2 Discoverer
1.3 Etymology
From Greek tephra, ashes from Indo-European base, to burn
From Old French esclate, from esclat (French éclat)
1.4 Class
Igneous Rocks
Metamorphic Rocks
1.4.1 Sub-Class
Durable Rock, Hard Rock
Durable Rock, Medium Hardness Rock
1.5 Family
1.5.1 Group
1.6 Other Categories
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock