1 Definition
1.1 Definition
Shale is a fine-grained sedimentary rock which is formed by the compaction of silt and clay-size mineral particles
Dacite is a volcanic igneous rock which is rintermediate in composition between andesite and rhyolite
1.2 History
1.2.1 Origin
Unknown
Romania and Moldova, Europe
1.2.2 Discoverer
1.3 Etymology
From German Schalstein laminated limestone, and Schalgebirge layer of stone in stratified rock. From Old English scealu in its base sense of- thing that divides or separate,
From Dacia, a province of the Roman Empire which lay between the Danube River and Carpathian Mountains where the rock was first described
1.4 Class
Sedimentary Rocks
Igneous Rocks
1.4.1 Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Soft Rock
1.5 Family
1.5.1 Group
1.6 Other Categories
Fine Grained Rock, Opaque Rock
Fine Grained Rock, Medium Grained Rock, Opaque Rock