Colored Stone Mining and Distribution

Unlike diamonds which are controlled by a few major mining companies, the most influential of which is DeBeers, colored stone prices are predominantly influenced by free market conditions. Colored stone deposits are usually worked by small scale independent miners. Production costs are relatively inexpensive compared to the tens or even hundreds of millions of dollars that can be invested into a diamond mine during its production life. Colored stone miners often sell their rough in markets that are visited by international cutters. The price will be negotiated based on supply and demand.

Recently, producing nations have become increasingly aware of the value of their mineral wealth and are exerting more influence over its production. More governments are joining in partnership with the private sector in exploration and mining. The aim is for a greater percentage of the mineral wealth to benefit the host nations. Traditionally, gem rough was either seriously undervalued or smuggled out of countries by dealers aiming to avoid export fees and taxes. As a result, virtually no benefit was derived by the populations living in the host countries.

Gem rough can be mined from both primary and secondary deposits. A primary deposit is one in which the gem crystals are still contained in the host rock. Mining of this type involves pits or tunnels that follow the gem-bearing vein. The gem rough is extradited from the host rock using tools, chemicals, or explosives. Most colored stone rough is mined from secondary deposits. That is to say the deposit of rough is located in an area other than where the gem rough was formed and transported toward the surface. Secondary deposits are areas where the rough has been transported to and deposited after being freed from its host rock by natural processes including weathering or erosion. Often these deposits can be active or dried riverbeds.

Unlike the open pit and underground mining associated with the Earth’s largest diamond mines, colored stone deposits are often mined with little more than a shovel, bucket and rope and a kerosene generator to pump air into the tunnel. If the deposit is associated with an active river or stream, mining may consist of shoveling gravel into a pan or sieve where any gem crystals present are extracted by hand. This is an extremely time consuming and laborious process. Once mined, rough gems eventually end up in one of the world’s main cutting centers, for colored stones, usually Thailand or China. However, more nations that host gem deposits are investing in the development of cutting centers as a means of adding value to and increasing the benefit derived from their mineral resources.

Madagascar is a good example of one such nation. Although mineralogically rich, this island nation located off the east coast of Africa had the distinction of being the third poorest country on Earth. However, in 2003 with financing from the World Bank, Madagascar launched an initiative to retain the wealth that its resources represented and stem the illegal smuggling of rough out of the nation. The consultant working for the government developed and launched gemology and stone faceting programs designed to assist the Malagasy people gain careers in the international gem trade. Now, many of the gems mined in Madagascar are also cut and polished in Madagascar. These programs have been highly successful and serve as models for other regions on the continent.