1 Definition
1.1 Definition
Ijolite is an intrusive igneous rock which is composed mainly of nepheline and an alkali pyroxene, usually aegirine-augite
Dacite is a volcanic igneous rock which is rintermediate in composition between andesite and rhyolite
1.2 History
1.2.1 Origin
Finland, Europe
Romania and Moldova, Europe
1.2.2 Discoverer
1.3 Etymology
From the first syllable of the Finnish words Ii-vaara, Iijoki, &c. commonly used geographical names in Finland, and the Gr. Xiflos, a stone
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
Igneous 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
Coarse Grained Rock, Opaque Rock
Fine Grained Rock, Medium Grained Rock, Opaque Rock