Editor’s Note
This article explains the fundamental density-based separation process used in gemstone mining, tracing the historical adoption of the jig apparatus from Australian tin fields to Southeast Asian gem operations.
Every type of mine requires washing the gravel with water to separate gemstones from worthless rock. The principle remains constant: utilizing the higher density of gemstones, water is used to wash away lighter materials. This is typically accomplished using a jig (an apparatus for separating ore from gem material), originally designed by Australian tin miners and later introduced to Thailand and Myanmar.
The gem quality is noticeably lower, as most of the superior material is discreetly sold by dealers to established clients. What often astounds visitors at gem markets are the Kanase women, wearing hats and colorful attire, selling their products. It’s common to see both women and men selling gems while wearing motorcycle helmets, adding a trendy sales twist. Serious traders generally carry gem torches and occasionally head-mounted loupes.
Since 2003, the U.S. ban on imports of Burmese gems, coupled with the closure of the Mogok mining area by the Myanmar military, has led to a sharp decline in the quantity of Burmese spinel on the international market. It is now difficult to obtain information on gem mining in Myanmar. Although red spinel has been discovered in other origins, Mogok remains the best-known source for small to medium-sized, pure red spinel.
Myanmar’s Mogok is perhaps the world’s most exotic and romantic gemstone origin. The romance of colored gemstones stems from their beauty, the mystique of their origins, the adventure of their discovery, and the moving stories of treasure seekers. Throughout history, this has continuously endowed gemstones with an irresistible allure.
Myanmar is one of the world’s largest gem producers, always exuding an “irresistible charm”—numerous mines, rows of gem and jade shops, dazzling displays of various gemstones, and the world-famous “Mogok Gemstone Belt”!
Besides Mogok, Mandalay—Myanmar’s second-largest city—cannot be ignored. It is the economic center of Upper Myanmar, the country’s last royal capital, and also a hub for the bustling jade market. Manufacturers sell raw jadeite, and polish and sell finished jade pieces as well as jade-set jewelry. Local dealers, foreign dealers, and tourists gather in the crowded, bustling market streets, where deals are struck, and jade is sawn, carved, and polished.
Why is Mogok so captivating? Why does it yield such quantity and variety of gems? The answer lies in geology. Observing the terrain of the Mogok Stone Tract is like witnessing a real geological marvel. This is one of the world’s most interesting and diverse gem-producing areas, where many geological events have occurred.
The most striking feature of the geological environment is the impressive blackened marble spires formed by weathering. This marble is found throughout the gem mining area in varying sizes. Removing the black, weathered surface reveals the white marble inside. Ruby and spinel typically form within marble. The collision of the Indo-Australian plate with the Eurasian plate was a major geological event.
For those who have witnessed colored gemstone mines worldwide, Mogok’s gem deposits are truly eye-opening. Several different types of mining operations are underway to suit each specific deposit. Alluvial mining of gem-bearing gravel (called byon) and hard-rock mining of ruby and spinel from marble are practiced.
Most of the easily accessible byon in the valley bottoms has been mined. Today, mining has spread to the hillsides and mountains around Mogok and Kyatpyin, and beyond. Alluvial, open-pit, cave and fissure, shaft, and adit hard-rock mining are all conducted, often in close proximity.
In recent years, Burmese rubies have consistently achieved dazzling results at international auctions.
– A 15.03ct ruby ring sold for CHF 12,751,500 (approx. HKD 99,913,613) at Christie’s Geneva in May 2017.
– A 13.26ct ruby ring by BHAGAT sold for HKD 81,662,500 at Sotheby’s Hong Kong in October 2017.
– A ruby and diamond ring by HARRY WINSTON, featuring a cushion-shaped ruby weighing approximately 22.86 carats (from Myanmar, unheated), sold for CHF 7,198,500 (approx. HKD 56,410,051) at Christie’s Geneva in May 2019.
Ruby: As the premier Burmese gem, it consistently holds the top position in the colored gemstone auction market. Myanmar has two ruby origins: Mogok and Mong Hsu. Mogok rubies have been renowned worldwide for over 2000 years. All record-breaking rubies at Christie’s and Sotheby’s originate from the Mogok mines. “Pigeon’s Blood” was once considered exclusive to Burmese rubies, specifically those from Mogok.
Sapphire: Also found in Myanmar, contributing to the country’s status as a major gem source.