The Pyaung Gaung (Clear Head) mines are famous for producing peridot of all qualities and sizes. At this time, there are two major peridot mines at Pyaung Gaung both operated by the UMEHL, which maintains a full logistics base and mining camp in the area complete with helipad. In November 2001, more than 70 miners were working at the open-pit deposit at mine #1 situated at the base of the Pyaung Gaung hill. Nearly all mining takes place from open-pits, where most peridots are found in situ in their parent rocks. A few small tunnels were drilled in the past at several locations, but this way of recovering gems has not been economically viable. Mine #2 is situated northeast of mine #1 and started in 2006 using improved tunelling methods of mining.
The peridot-bearing rocks are hauled in trucks and transported to a high-security washing-recovery plant. The workers there use four-pound hammers to break the parent rock and retrieve the peridot crystals embedded therein.
The upper-grade peridots found in Pyaung Gaung are considered the finest in the world, not only in color, but also in large size. Production figures on peridots are not available. It appears that the stones are mined in accordance with market conditions and demand.
In the same general area of Pyaung Gaung and Zalat-taung
, gem quality star peridot, greenish-brownish, dark green to green, and brownish enstatite, greenish hornblende, and green-blue chrysoprase are also found. These gems are recovered in open-pit and lebin
mining schemes from alluvium at the base of Pyaung Gaung and Zalat-taung hills, at the Bernardmyo valley and surrounding areas.
Ref: Ted Themelis (2008) Gems & mines of Mogok, p. 176