1 Definition
1.1 Definition
Essexite which is also known as nepheline monzogabbro, is a dark gray or black holocrystalline plutonic Iigneous Rock
Shale is a fine-grained sedimentary rock which is formed by the compaction of silt and clay-size mineral particles
1.2 History
1.2.1 Origin
1.2.2 Discoverer
1.3 Etymology
From the locality in Essex County, Massachusetts,US
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,
1.4 Class
Igneous Rocks
Sedimentary 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
Fine Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock