1 Definition
1.1 Definition
Scoria is a dark-colored extrusive igneous rock with abundant round bubble-like cavities
Mudstone is a fine-grained, dark gray sedimentary rock, which is formed from silt and clay and is similar to shale but has less laminations
1.2 History
1.2.1 Origin
1.2.2 Discoverer
1.3 Etymology
From late Middle English (denoting slag from molten metal), from Greek skōria refuse, from skōr dung
From the English mud and stone, from low German mudde and stainaz
1.4 Class
Igneous Rocks
Sedimentary Rocks
1.4.1 Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Soft Rock
1.5 Family
1.5.1 Group
1.6 Other Categories
Fine Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock