They flash, they sparkle and they catch the eye. They have been globally marketed successfully as the precious gems of choice to symbolize eternal love. Born of fiery explosions deep within the earth’s crust millions of years ago, they are tiny crystals of carbon. They are painstakingly prospected and carefully extracted around the globe in the arctic tundra, tropical forests, barren deserts and ocean coasts to be cut and polished into a myriad of styles and shapes. They’re diamonds, and they’re universally and sentimentally cherished by millions.
The Evolution of Diamonds
The name “diamond” derives from the ancient Greek word, adamas, meaning “invincible.” The hardiness of diamonds (their inability to be scratched) and their capability to disperse light makes them useful for industrial cutting applications, and makes them exceptionally ideal for jewelry that is worn daily, such as engagement rings and wedding bands. Diamonds polish extremely well and they retain their luster. When found in river beds in ancient India, these gems were treasured as religious icons. In early civilizations in Brazil they were used as engraving implements. They remained rare until the late 19th century, when the first diamond deposit was discovered in 1870 in South Africa near the Orange River. About 50 percent of the diamonds mined today originate in central and southern Africa, with the other significant sources being Russia, Canada, Australia and India, and, to a lesser extent, Brazil.
Diamond deposits are found inside the earth’s mantle miles deep, encased in host rock material called kimberlite and lamproite. Millions of years ago, high pressure and high temperature enabled the formation of crystals. A series of underground explosions then sent lava shooting up closer to the surface of the earth, which cooled and hardened into long pipe-like formations. This igneous rock hosts the diamond crystals that came gushing up with the lava.
An increase in the scientific knowledge of diamond formation, potential deposits and mining technology has led to an increase in the supply of diamonds on the world market today whencompared with their former rare discovery in alluvial deposits in riverbeds and coastal areas. A combination of improved cutting and polishing techniques, growth in the world economy and successful targeted advertising campaigns have all added to a growing demand for these precious gems.
An intricate network of controlled production and demand activities keeps the value of diamonds at a consistent level, an even keel very different from the fluctuations in market prices seen with other precious commodities such as silver and gold. With a tight association of leaders in mining, gem labs and retail distributors, the industry also is able to monitor its environmental and social activities and take remedial actions when required. In 2000, members of the World Federation of Diamond Bourses and the International Diamond Manufacturers Association established the World Diamond Council to specifically prevent the trading of diamonds, often referred to as “conflict diamonds,” that are used to fund war and inhuman acts.
The weight of a diamond, which is measured in carats, is based on the ancient weight measurement of a carob seed, weighing only 1/200th of a pound. Even with modern technology, the mining of diamonds can be compared to the proverbial search for the needle in the haystack.
The 4 Cs: Color, Clarity, Cut and Carat
The Gemological Institute of America, now headquartered in Carlsbad, California, developed the first internationally accepted diamond grading system in 1953. Known as the “4Cs,” the system provides unbiased expert opinions of the quality of polished diamonds by applying uniform criteria based on color, clarity, cut and carat weight.
“Of all the diamonds mined, only one percent of them are gem quality,” says certified gemologist, Dwight Tom, in Philadelphia, Pennsylvania. “Therefore, out of 100 carats, only one gem is gem quality that can be made into a jewel, and the rest are commercial diamonds for use in cutting devices like diamond tips for tools.”
Environmental Challenges and Practices
In order to minimize the impact on the environment, the diamond mining industry uses modern methods and a clinical approach to its activities in mineral extraction. The disturbance of the land is a key challenge when large quantities of soil are removed. It is in the best interests of environment and commercial organizations to see that all mining is accomplished within the most efficient footprint on the land for the least disturbance. Best practices require an environmental impact plan for removal, storage and return of top soil to mitigate the effects of the disturbance and allow the area to return to its previous state. Besides land disturbance and the impact on the biodiversity – the maintenance of the balance of humans, plants and animals in the region – other challenges associated with diamond mining include energy use and emissions, use of water, rock waste and recycling. Unlike other industrial mining processes, diamond mining does not require chemicals for extraction, but water is needed.
There are several different types of diamond mining methods used, depending upon the location of the deposit. The environmental management plan, including its mitigation activities, will vary according to the mine’s geographical, ecological and social situation. When exploration takes place, the minimum amount of soil is extracted during the sampling/drilling process, topsoil is replaced and refilled afterwards, and all man-made or vehicle tracks are reused when possible. After exploration, one of the following mining activities best suited to the location is employed—open pit and underground, coastal and inland alluvial, and marine.
With open pit mining, which can be done near the earth’s surface, large quantities of surplus waste rock, sand, soil and processed kimberlite can accumulate in the adjacent areas. Rehabilitation then requires removal, storage and return of the topsoil. In coastal areas, it may be necessary to construct seawalls and remove plant life as well as topsoil and sand. Once the mining is completed, plant life and soil is replaced. Wind and wave motion over time restores the surrounding land, but often re-vegetation is necessary. When native plant life around a mining site is harvested, seeds can later be replanted to keep the native species healthy and unaffected. Mining companies work with the Millennium Seed Bank, run by The Royal Botanic Gardens at Key Gardens in London, England, on a global seed conservation program. The industry also supports and runs wildlife conservation projects when local wildlife can be sensitive to habitat disturbances. Minimizing mining’s impact on these ecosystems is articulated throughout the entire process from exploration through reclamation activities after the mine has been closed.
