Definition
Mudstone is a fine-grained, dark gray sedimentary rock, which is formed from silt and clay and is similar to shale but has less laminations
Rhyolite is a fine-grained igneous rock which is rich in silica
History
Origin
-
North America
Discoverer
William Smith
Ferdinand von Richthofen
Etymology
From the English mud and stone, from low German mudde and stainaz
From German Rhyolit, from Greek rhuax lava stream + lithos stone
Class
Sedimentary Rocks
Igneous Rocks
Sub-Class
Durable Rock, Soft Rock
Durable Rock, Hard Rock
Family
Group
-
Volcanic
Other Categories
Fine Grained Rock, Opaque Rock
Coarse Grained Rock, Opaque Rock