A pound of radium is worth about 10,000,000. The biggest gem diamond ever found weighed about one and a third pounds and its price was $3,000,000. Smaller and less perfect diamonds are far less costly, A necklace of quality rubies or emeralds might be more valuable than a similar necklace of diamonds. But though diamond is not the most priceless substance, it is very valuable and there are sound reasons why this is so.

A substance may be valuable because it is rare and hard to come by, because it is beautiful, durable or useful. The diamond is the hardest and the most brilliant of all the natural substances   which makes it durable and beautiful. Its hardness makes it useful, for it can be used to cut or polish any other natural substance   which means that the smallest, most imperfect diamond can depend upon having a steady job in industry where it is used in cutting, drilling and polishing tools.

These qualities make it worth while to hunt for diamonds, but here we run into another snag which makes them even more valuable. Mother Nature was very stingy with them. What’s more, she hid them deep in the earth’s crust. A few diamonds have been found by chance in stream beds, but these have been washed away from their original hiding places.

 The bed rock in which a valuable mineral is found is called the matrix. Diamonds may be found in a hard, bluish clay called kimberlite. This matrix is formed by the weathering of old lava flows, and diamonds, we are told, form from carbon crystalized in the heat and pressure of volcanic activity. They are found buried deep in volcanic vents or pipes which later have been plugged by rock made by a matrix such as kimberlite.

The Kimberly diamond field of South Africa is the world's most important, and its main shaft is almost a mile deep. Some 2,000 tons of matrix rock must be dug and sifted to yield just a few diamonds. The yield of big and little diamonds is then sorted and graded by an expert  and most of them have flaws which make them fit only for industrial work. A rare gem stone, sizable and perfect, is cut and polished by another expert and a few of these stones will shatter under treatment. All this work, those special skills and expensive machinery add to the price of the diamonds. Extra glamor value is added because the precious stones are the most durable, the most brilliant and, some say, the most beautiful of all jewels.

Our clever chemists have copied natures recipe for making diamonds, with some success. Compounds of carbon are heated to 5,000 Fahrenheit degrees and squeezed under 750 tons of pressure to the square inch. This treatment is very expensive and so far our man made diamonds are small fragments which are suitable only for industrial work.