Corundum was first discovered in Malawi in the 1950s. Today, a majority of the rubies exported from the country come from a single mine, the Chimwadzulu Hill mine, which is located in the south-central part of the country. Malawi lies on the Mozambique Belt, an extremely prominent geological formation rich in gemstone deposits. Although located in such a prime location, Malawi is one of the poorest nations in Africa.
The deposits at Chimwadzulu are eluvial, which means that when gems eroded out of their source rock, they were transported only small distances. The deposit can be mined during the dry season from April to October. The mining area is steep, making it difficult to employ heavy equipment. Nevertheless, the mine now produces about five kilograms of gem-quality rough per month, and about a third of the yield is ruby.
The Chimwadzulu mine is controlled by a private company, which is currently inventorying the size of the deposit. To survey for fresh material, test trenches or pits are opened in an effort to discover new gemstones. To date, approximately 2000 three-meter test pits have been dug.
The rubies from Chimwadzulu Hill are typically orange red to vivid red and they lack silk. They do not require heat treatment to enhance their color. Untreated material from Chimwadzulu Hill is often marketed overseas as Nyala ruby. It is named after a rare nyala antelope, which is indigenous to the area where the gems are mined.
The country continues to struggle to develop, and many view the ethical handling of the country’s gemstones to be part of the solution. As the government works with mining companies, there is incredible opportunity for communities and economies to vastly improve and establish a market presence for Malawi.
Next, we explore the very heart of the geological phenomenon known as the Mozambique Belt in Ruby Mines in Mozambique.