1 Definition
1.1 Definition
Pumice is a volcanic rock that consists of highly vesicular rough textured volcanic glass, which may or may not contain crystals
Chalk is a soft, white, powdery limestone consisting mainly of fossil shells of foraminifers
1.2 History
1.2.1 Origin
1.2.2 Discoverer
1.3 Etymology
From Old French pomis, from a Latin dialect variant of pumex
From old English cealc chalk, lime, plaster; pebble, from Greek khalix small pebble, in English transferred to the opaque, white, soft limestone
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