Several mining sites are located in the heavily populated quarters of Pan-ma. Rubies
, blue, yellow and bi-colored sapphires
were found in the alluvium, using large-scale open-pit mechanized methods. Most of these gems are small but of good quality, suitable for faceting as well as for cabochons. In 2000 a magnificent blue sapphire of 53 carats was recovered. In September 2001 the mines were closed, but they reopened in 2005.
Ref: Ted Themelis (2008) Gems and Mines of Mogok, p. 247