Pumice Reference Libraries
Scoria is a term used by geologists to describe an igneous rock containing many gas bubbles, or vesicules. Scoria forms when magma rich in dissolved gases is vented. As the magma encounters lower pressures, the gasses are able to escape and form bubbles. These bubbles are trapped when the magma cools and solidifies. Volcanic cones of scoria can be left behind after eruptions, usually...
- Bad luck; misfortune.
- The smallest amount possible or the most worthless thing.