Geographical Location

Mong Hsu is located about 250 km (150 miles) southeast of Mogok, at an elevation of 700 m above sea level. It can be reached from Taung Gyi, the capital of Shan State, by traveling over a rough road for about 14 hours.

Secondary (alluvial) corundum deposits are found in the terraces of Nam Hsu River, southeast of Mong Hsu township. These river terraces, where the first rubies were discovered and where mining and prospecting started, are 4 km long and 0.8 km wide, trending from northwest to southeast, and 80-160 m deep. In 1992, about 2,000 miners were working these alluvial deposits.

Additional secondary deposits have been found 16 km (10 miles) farther southeast. These extend over an area more than 100 square km between the two mountains Hsan Tao and Loi Paning. The "government prospecting area" is restricted to a central 0.8 square km portion.

By 1994, about 500 joint ventures between private individuals and the Myanmar government were operating in the region, literally chewing up the surrounding hills.

Alluvial ruby is also found at Loi Khan and Mong Sang, which lie southwest and south (respectively) of Mong Hsu.