Definition
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Discoverer
Etymology
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Other Categories
Arkose is a sedimentary rock, specifically a type of sandstone containing at least 25% feldspar
From Auvergne region of France used by a French geologist Alexandre Brongniart in 1826 who applied this term to some feldspathic sandstones
Coarse Grained Rock, Opaque Rock
Tuff is a type of rock made of volcanic ash ejected from a vent during a volcanic eruption
From a Latin word tophous then in Italian tufo and finally tuff
Durable Rock, Medium Hardness Rock
Fine Grained Rock, Opaque Rock