Definition
Luxullianite is a rare type of granite, known for presence of clusters of radially arranged acicular tourmaline crystals which are enclosed by phenocrysts of orthoclase and quartz in a matrix of quartz, tourmaline, alkali feldspar, brown mica.
Taconite is a low-grade iron ore which belongs to sedimentary rock and containing about 27% iron and 51% silica
History
Origin
England
Western Australia, Minnesota
Discoverer
Unknown
Newton Horace Winchell
Etymology
From the village of Luxulyan in Cornwall, England, where this variety of granite is found
From the name of Taconic Mountains in New England
Class
Igneous Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Medium Hardness Rock
Family
Group
Plutonic
-
Other Categories
Coarse Grained Rock, Opaque Rock
Coarse Grained Rock, Opaque Rock