Carbon as diamond is the most expensive and brilliant of all the natural gemstones and the hardest of the naturally occurring abrasives. In microcrystalline and nearly amorphous form, it is used as a black pigment, as an adsorbent, as a fuel, as a filler for rubber, and, mixed with clay, as the “lead” of pencils.
Because it conducts electricity but does not melt, graphite is also used for electrodes in electric furnaces and dry cells as well as for making crucibles in which metals are melted.
Pure diamond is the hardest naturally occurring substance known and is a poor conductor of electricity.
The Rochester Museum and Science Center (RMSC) is the repository for about half of the assemblages from the New York sites in our project.
Thanks to the amazing staff at RMSC, who approved our request to conduct radiocarbon dating and consistently facilitated our research, we have finished collecting all of our samples from RMSC.
A fourth form, called Q-carbon, is crystalline and magnetic.
Yet another form, called amorphous carbon, has no crystalline structure.
Although widely distributed in nature, carbon is not particularly plentiful—it makes up only about 0.025 percent of Earth’s crust—yet it forms more compounds than all the other elements combined.