Definition
Origin
Discoverer
Etymology
Class
Sub-Class
Group
Other Categories
Scoria is a dark-colored extrusive igneous rock with abundant round bubble-like cavities
From late Middle English (denoting slag from molten metal), from Greek skōria refuse, from skōr dung
Durable Rock, Medium Hardness Rock
Fine Grained Rock, Opaque Rock
Felsite is a very fine grained volcanic rock that may or may not contain larger crystals and light colored rock that typically requires petrographic examination or chemical analysis for more precise definition
From English feldspar and -ite
Durable Rock, Medium Hardness Rock
Fine Grained Rock, Opaque Rock