Diamond and graphite occur naturally on Earth, and they also can be produced synthetically; they are chemically inert but do combine with oxygen at high temperatures, just as amorphous carbon does.
Fullerene was serendipitously discovered in 1985 as a synthetic product in the course of laboratory experiments to simulate the chemistry in the atmosphere of giant stars.
Yet another form, called amorphous carbon, has no crystalline structure.
Other forms—such as coke—are sometimes called amorphous, but X-ray examination has revealed that these substances do possess a low degree of crystallinity.
Carbon as an element was discovered by the first person to handle charcoal from fire.
Thus, together with sulfur, iron, tin, lead, copper, mercury, silver, and gold, carbon was one of the small group of elements well known in the ancient world.
It was later found to occur naturally in tiny amounts on Earth and in meteorites.
, “to write,” reflects its property of leaving a dark mark when rubbed on a surface.
Molecules of fullerene show promise in a range of applications, including high-tensile-strength materials, unique electronic and energy-storage devices, and safe encapsulation of flammable gases, such as hydrogen.
The following products result: (1) diamond proper—distorted cubic crystalline gem-quality stones varying from colourless to red, pink, blue, green, or yellow; (2) bort—minute dark crystals of abrasive but not gem quality; (3) ballas—randomly oriented crystals of abrasive quality; (4) macles—triangular pillow-shaped crystals that are industrially useful; and (5) carbonado—mixed diamond–graphite crystallites containing other impurities.
The successful laboratory conversion of graphite to diamond was made in 1955.
(Coals are elemental carbon mixed with varying amounts of carbon compounds.
Coke and charcoal are nearly pure carbon.) In addition to its uses in making inks and paints, carbon black is added to the rubber used in tires to improve its wearing qualities.