In 1772 he pooled resources with other chemists to buy a diamond, which they placed in a closed glass jar.
They focused the sun’s rays on the diamond with a remarkable giant magnifying glass and saw the diamond burn and disappear.
Lonsdaleite is a diamond-like carbon network which has graphite’s hexagonal structure.
It is made when meteorites containing graphite hit another body, such as Earth.
The buckyballs arrived in comets or asteroids and have been discovered in rocks associated with the Permian-Triassic mass extinction 250 million years ago. A wonderful image released by Michael Ströck under the GNU Free Documentation License: The structures of eight allotropes of carbon: a) Diamond b) Graphite c) Lonsdaleite d) C60 (Buckminsterfullerene) e) C540 Fullerene f) C70 Fullerene g) Amorphous carbon h) Single-walled carbon nanotube. Harmful effects: Pure carbon has very low toxicity.
Inhalation of large quantities of carbon black dust (soot/coal dust) can cause irritation and damage to the lungs.
In 1985, Robert Curl, Harry Kroto and Richard Smalley discovered fullerenes, a new form of carbon in which the atoms are arranged in soccer-ball shapes.
The best known fullerene is buckminsterfullerene, also known as C60, consisting of 60 carbon atoms.
The structures of eight allotropes are shown at the bottom of this page.
Note: At normal atmospheric pressure, carbon does not melt when heated, it sublimes. it undergoes a phase change directly from solid to gas.
If the pressure is increased to 10 atmospheres carbon (graphite) is observed to melt at 3550 °C.
Graphite is used for pencil tips, high temperature crucibles, dry cells, electrodes and as a lubricant.
Diamonds are used in jewelry and – because they are so hard – in industry for cutting, drilling, grinding, and polishing.