1 Definition
1.1 Definition
Essexite which is also known as nepheline monzogabbro, is a dark gray or black holocrystalline plutonic Iigneous Rock
Blueschist is a metamorphic rock which is generally blue in color and is formed under conditions of high pressure and low temperature
1.2 History
1.2.1 Origin
1.2.2 Discoverer
1.3 Etymology
From the locality in Essex County, Massachusetts,US
From French schiste, Greek skhistos i.e. split
1.4 Class
Igneous Rocks
Metamorphic 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, Medium Grained Rock, Opaque Rock