Diamonds The Hardest of Minerals
What do a glittering diamond and a lead pencil have in common? Diamonds are very hard and the graphite of the pencil’s tip is very soft. These two different substances contain a wonderful proof of creation called carbon.
A rough, unpolished diamond is the hardest of all minerals.(1) For this reason, a crystal diamond is used to cut and to drill all kinds of material and is also used as an abrasive to smooth surfaces. (2)
Hardness is the resistance of a mineral to scratches from outside forces; it is easy to recognize minerals by this trait. By scratching one mineral with another, their relative hardness can be determined. Scientists use a point system to designate the hardness of all minerals. They rate diamonds with the highest ratio of ten over ten. So, what makes diamonds so hard?
It is very interesting that the soft, breakable graphite in a pencil tip is made up of the same atoms as a diamond. Graphite is composed of the same carbon atoms as a diamond. But, while one is very soft, the other is extremely hard. One is as black as a lump of charcoal; the other may be sparkling bright. One is commonly found in nature; the other is rare. For all these reasons, diamonds are much more valuable than graphite. How is it then, that carbon atoms can be so different from one another?
Carbon: The Foundation of Life
(The Value of Diamonds is Determined by its Atoms)
Before we consider the differences, we must speak about the carbon atoms that make up a diamond. The carbon atom is very important for living creatures. Nevil Sidgwick, the English chemist, states the following in his book, Chemical Elements and Their Compounds:
Carbon is unique among the elements in the number and variety of the compounds which it can form. Over a quarter of a million have already been isolated and described, but this gives a very imperfect idea of its powers, since it is the basis of all forms of living matter. (3)
The class of compounds formed exclusively from carbon and hydrogen are called hydrocarbons. This is a huge family of compounds that include natural gas, liquid petroleum, kerosene, and lubricating oils. The hydrocarbons ethylene and propylene form the basis of the petrochemical industry. Hydrocarbons like benzene, toluene, and turpentine are familiar to anyone who has worked with paints. The naphthalene that protects our clothes from moths...