Elements:
a pure substance containing only one kind of
an element be separated into simpler materials (except during nuclear reactions).
over 100 existing elements are listed and classified on the

compounds:
a pure substance containing two or more kinds of
the atoms are combined in some way.
compounds be separated by physical means.

mixtures:
two or or not chemically combined.
mixtures can be uniform( and are known as solutions
mixture can also be non-uniform (called

answer is: naturally occurring solid, inorganic compound or element is mineral.

minerals usually have crystalline form, that means than crystal constituents (atoms, molecules or ions) are arranged in a highly ordered microscopic structure, forming a crystal lattice that extends in all directions.

for example magnetite is a mineral of iron oxide (fe₂o₃).

calcite is a carbonate mineral and the most stable polymorph of calcium carbonate (caco₃).

dolomite is an   carbonate mineral composed of calcium magnesium carbonate (camg(co₃)₂).

water at room temperature is flowing through a pipe with pressure taps located 10 ft apart along one section of the pipe, which are connected to a mercury (s=13.6) manometer.