1 Definition
1.1 Definition
Essexite which is also known as nepheline monzogabbro, is a dark gray or black holocrystalline plutonic Iigneous Rock
Coquina is a sedimentary rock that is composed either wholly or almost entirely of the transported, abraded, and mechanically-sorted fragments of the shells of molluscs, trilobites, brachiopods, or other invertebrates
1.2 History
1.2.1 Origin
USA
European Foreland Basins
1.2.2 Discoverer
1.3 Etymology
From the locality in Essex County, Massachusetts,US
From Concha (Latin)+ Coquina(Spanish) +conch(English)= Couquina (mid 19th century)
1.4 Class
Igneous Rocks
Sedimentary Rocks
1.4.1 Sub-Class
Durable Rock, Hard Rock
Durable Rock, Soft Rock
1.5 Family
1.5.1 Group
1.6 Other Categories
Fine Grained Rock, Opaque Rock
Coarse Grained Rock, Opaque Rock