Did you ever wonder what happens to a diamond from the mine to the jewelry store?

By David McClelland

We just returned from a Caribbean Cruise where the on-board shopping gal told us something of the journey of a diamond from the mine to the jewelry store. I just did the research and I thought
it was interesting. I will share what I learned here with you. You won't believe how long and complex the diamond's journey is.

A diamond's journey began deep within the earth – 100 to 200 miles below the surface. Diamonds were formed up to 3.3 billion years ago as a result of unimaginable heat and pressure that were placed upon carbon crystals there.

Powerful volcanic activity formed what are known as "pipes" – openings in the earth – and the immense pressure forced the diamonds up through the pipes to the surface, along with other minerals such as kimbertite. Some of these diamonds made their way into streams, rivers and seas; however, these are considered to be only secondary deposits. Most of the diamonds forced up through the earth settled back into the kimbertite pipes – and it is these primary sources that have been the basis of the world's diamond mines. Only one in 200 kimbertite pipes contains diamonds in economically viable quantities.

Once discovered, diamonds can be difficult to mine. Estimates are that it takes over 250 tones of ore to produce just one carat of rough diamond. The ore goes through many stages of blasting, crushing and processing, including advanced x-ray techniques, to release the diamond. More that 120 million carats are mined each year, but only about 30 million, or about ¼ of the stones mined, are considered gem quality.

Although diamonds are found in numerous locations around the world, about 80% come from Australia, Botswana, Canada, Namibia, South Africa and Russia.

Once the diamonds have been mined and processed, the next step is to sort, classify, and value them according to their size, shape, quality and color. De Beers' marketing arm, DTC, sorts some two-thirds of the world's diamonds by value and then into more than 16,000 categories. They are then sold ten times a year at regular, invitation-only, sales called "sights" to the world's leading diamond cutters, polishers and manufacturers. Sightholders may choose to cut the rough they buy themselves or may sell some percentage to smaller manufacturers or wholesalers.

The next step for the rough diamond is cutting and polishing. This takes great skill, with meticulous techniques that have been practiced for generations. The main diamond cutting and trading centers are based in Antwerp, Belgium; Mumbai, India; Tel Aviv, Israel; New York; and Johannesburg, South Africa. China and Thailand have most recently developed their own centers.

Although some of the polishing process is computerized, most of the work is still performed by hand. Initially, the cutter uses cleaving, sawing or laser cutting to separate the original rough into smaller, more workable pieces. Then, the girdler uses a process called bruting that grinds away the stone's edges and provides its outline shape. Faceting follows, usually in two steps. The first 18 facets (table, culet, bezel, and pavilion of a stone) are cut and polished by a blocker. The brillianteer cuts and polishes the final 40 facets, including the star, upper girdle and lower girdle. Finally, the cut gem is boiled in acids to remove dust and oil. Once polished, most diamonds are sold and traded in the 24 registered diamond bourses around the world.

At this point, the polished gems are ready to be set into finished pieces of jewelry, which is the manufacturer's responsibility. The pieces are then sold to either a wholesaler, who works as a middleman to sell the manufacturer's goods to the retailer, or directly to the retailer by the manufacturer.

Now, the finished diamond goes on display in a jewelry store near you. Then comes the part where you walk by the jewelry store window and a beautiful diamond grabs your eye and you either shrug and keep on walking or your enter the store to take a closer look. Did you ever guess that a diamond's journey was so far and took so long? Whew!!!