Gwebin (Gwe Tree), Kyauk-Pyat-That, Mogok Township, Pyin-Oo-Lwin District, Mandalay Region, Myanmar
The principle mines are located in the north side of the Mogok-Mandalay road.In 2001 the gems were mined in open-pit schemes. Rubies of all qualities and sizes, usually small, are found in the alluvium with red, pink and green spinels. Few high quality and large size blue sapphires are recovered. The principle rocks are quartzite, leucogranite and marble.
During 1997-1999 mining period rubies and sapphires were mined in numerous lebin schemes.
The largest sapphire found in Gwebin weighed about 200 ct and was of good quality and faceting grade.
Ref: Ted Themelis (2008) Gems and Mines of Mogok, p. 265