What are three forms of the element carbon?

There are at least eight forms of carbon: amorphous, graphite, diamond, fullerenes, aggregated diamond nanorods, carbon nanofoam, glassy carbon, and linear acetylenic carbon.

Explanation:

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).

2b2t

explanation:

2b2t