Definition
Origin
Discoverer
Etymology
Class
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Other Categories
Taconite is a low-grade iron ore which belongs to sedimentary rock and containing about 27% iron and 51% silica
Western Australia, Minnesota
From the name of Taconic Mountains in New England
Durable Rock, Medium Hardness Rock
Coarse Grained Rock, Opaque Rock
Borolanite is a variety of Nepheline Syenite and belongs to igneous rocks and contains nepheline-alkali feldspar pseudomorphs which occur as conspicuous white spots in the dark rock matrix
From Alkalic Igneous complex near Loch Borralan in northwest Scotland
Durable Rock, Medium Hardness Rock
Fine Grained Rock, Opaque Rock