Definition
Origin
Discoverer
Etymology
Class
Sub-Class
Group
Other Categories
Rhomb-porphyry is a porphyritic igneous rock with abundant wedge or lens shaped anorthoclase or feldspar phenocrysts
From Latin term that means purple
Durable Rock, Medium Hardness Rock
Fine Grained Rock, Opaque Rock
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