Alabaster

Peat is partly decayed plant matter that has collected in swamps and marshes over long periods of time. It is generally the first stage in the… See more » Flint is a hard rock that ranges in color from brown to dark gray to black. It consists of tiny crystals of the mineral quartz. In most cases,… See more » Pyroxene, PY rok seen, is any of a group of minerals that play an important part in the formation of many kinds of rocks. Pyroxenes occur widely in… See more »