Scoria-- (Natural Brick rock) is somewhat porous, has high
surface area and strength for its weight with often has striking
colors. Scoria is often used in landscaping and drainage works. It
is in high demand in ND where oil drilling is taking place. It is used
to build roads to oil fields and to make oil pads as well as being
used for landscaping base material for construction sites
Scoria is a volcanic rock containing many holes or vesicles. It is
most generally dark in color (generally dark brown, black or red),
and basaltic or andesitic in composition.
Scoria is relatively low in mass as a result of its numerous
macroscopic ellipsoidal vesicles, but in contrast to pumice all
scoria has a specific gravity greater than 1 and sinks in water.