Carbonados.

Image: Wikipedia

I sing the praises of carbonados. The jewelry-class diamonds found in the Chapada Diamantina made it rich and famous (at least in its time), but the most important legacy of the region has actually been almost forgotten – the carbonados!

The shiny beauty of diamonds brought thousands of miners and camp followers to the Chapada Diamantina starting about 1844 (just a few years before the famous California gold rush). Boomtowns popped up in every corner of the mountains where rich strikes were discovered. It was hard brutal work undertaken by both freemen and slaves, but the rewards were fantastic for many. There are no truly reliable records of the quantities of diamonds found there. An excellent review of the diamond trade in Bahia state was compiled by xxxxxx. This author uncovered official data from various archives, but the small sizes of diamonds, and the cultural skills of Brazilians who have honed the ability to avoid taxes and other government regulations over many generations, assured that only a small fraction of the riches produced ever came near the taxman and bean-counters. 

But while diamonds may be pretty (and not even very rare in the world) the most important legacy of the Chapada Diamantina – and by far the least known – was its production of black diamonds.

When the early miners were searching for diamonds they would often encounter nondescript black stones that would pan out together with the gemstones. The fact that they settled to the bottom of the "bateias" – the large (up to almost a meter/yard in diameter), shallow, conical wooden pans that the miners used in the final step of diamond purification – identified them as "curiosities", really nothing more.

Legend has it that these strange little black stones were traded by slaves to the diamond buyers in exchange for cheap cigars. They were later passed around among diamond merchants in Europe, geologists, and toolmakers. But surely no one could imagine at first how important a role they would have in changing the world.

Diamonds, being incredibly hard, had found many industrial uses, but their ultimate utility was limited by their single-crystal nature. Diamonds are hard, very hard, but not "tough". If you hit them on the right spot along their crystal fracture plane they will split in two, like a huge boxer with a "glass jaw" who will go down when his lesser opponent catches him with an unpretentious upper-cut. Down and out.

At some point, a toolmaker put a carbonado into a tool bit – and the results blew him out of the water. Here was a stone as hard as (or even harder than) a diamond that could be used to work metals and stone without fracturing, without breaking. Eureka!

Now this was great in itself. But there was a synergism about to happen that would move human engineering and creativity to a much higher plane. Things were about to really take off.

In 1867 a Swiss industrialist and inventor came up with something called dynamite. Incredible explosive energy that could be packaged and safely used. Mr. Nobel's dynamite (later “gelignite” – check it out on Google) could now reach its true potential.

With the ability to easily drill bore-holes in the hardest stone with the new carbonado-tipped rock drill bit developed by Leschot (1862), a Frence inventor, modern transport and commerce changed forever. 

With the carbonados found essentially exclusively in the Chapada Diamantina, the dynamite supplied by Nobel, and the rock drills invented by Leschot the, train tunnels could be driven through the Alps, the Panama Canal linked two mighty oceans, the subways (metros) in London and France moved the populations of entire cities, and heavy industrial mining bloomed. Everywhere in the world the mountains and rocks that stood in the way of human travel melted away. The world was now malleable.

This was the Golden Age of Engineering. The Eiffel Tower (1889), the Panama Canal (1914), improvements in iron fabrication, concrete production, the mastery of electric power generation. The transition to the modern industrial age. Your iPhones, Internet, space technology, and everything you see around you are the legacies of thousands of nameless slaves and miners who moved incalculable tons of sand, stones, and mud to uncover the ugly, black, little stones that changed the world.

Posted in: Diamond Highlands