It is a classic geological basin, located at the north-western end of the Kathe-yaike hill, forming a basin 20 meters deep and 230 meters in diameter.
In 1993, a 275 meter-long water-drainage tunnel was built, so that mining operations could continue uninterrupted all year around. All mining currently takes place by means of a typical mechanized open-pit system. The overburden is washed through the tunnel using water cannon. The byôn
is transported to the on-site washing plant, which is equipped with a pulsating jig to recover gems.
At Loke-khet-inn, blue sapphires
, typical of Mogok origin, are mostly found, often of fine quality and in larger sizes, sometimes exceeding 1,000 carats. Good quality star blue sapphires
, yellow sapphires, zircons
are also found.
In the alluvium accumulated in the fracture-filled deposits, sapphire, some ruby
, zircon, topaz are found using letkya-dwin
mining methods. Accessory minerals include magnetite and limonite. Rubies and spinels
are recovered from different types of marble.
It is said that in this general area a 560-carat blue sapphire was mined, which was named the Jungle Sapphire (Themelis, 2000)
Ref: Ted Themelis (2008) Gems and mines of Mogok, p. 257