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
Schist is a medium grade metamorphic rock with medium to large, flat, sheet like grains in a preferred orientation
From French schiste, Greek skhistos i.e. split
Durable Rock, Medium Hardness Rock
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock