KATHA, a district in the Sagaing division of Burma, with an area of 8,917 sq.m., 3,73o of which consists of the former separate State of Wuntho. Katha now includes the former separate district of the Ruby mines. The district stretches from the main divide between the Irrawaddy and Chindwin valleys on the west to the border of the Shan States on the east. Three ranges of hills run through the district, known as the Minwun, Gangaw and Mangin ranges. They separate the three main rivers—the Irrawaddy, the Meza and the Mu. The Minwun range runs from north to south, and forms for a considerable part of its length the dividing line between the Katha district proper and what formerly was the Wuntho State. Its average altitude is between 1,500 and 2,000 feet. The Gangaw range runs from the north of the district for a considerable portion of its length close to and down the right bank of the Irrawaddy as far as Tigyaing, where the Myatheindan pagoda gives its name to the last point. Its highest point is 4,400 ft., but the average is between 1,50o and 2,000 feet. The Katha branch of the railway crosses it at Petsut, a village 12 M. W. of Katha town. The Mangin range runs through Wuntho (highest peak, Maingthon, feet).
Gold, copper, iron and lead occur in the district, but are not now worked. Jade and soapstone also exist, and salt is produced from brine wells. There are important forest reserves in Katha. The population in 1921 was 253,725, an increase of 8,128 in the decade. Burmese comprise nearly half the population, Shans (mostly in Wuntho and the hills east of the Irrawaddy) about a third, whilst nearly all the Sak (Lui) of Burma are in this district.
Rice is the chief crop in the plains, tea, cotton, sesamum and hill rice in the hills. The district was first occupied by British troops in 1886, but it was not finally quieted till 1890, when the Wuntho sawbwa was deposed and his State incorporated in Katha district. Wuntho and other parts of the district have evil reputations for fever.
The portion of Katha lying east of the Irrawaddy forms geo graphically a portion of the Shan plateau. Here, in the centre of a valley, 4,000 ft. above sea-level, and 61 m. by motor road from the river port of Thabeitkyin lies MogOk, the centre of the famous Ruby mines. Synthetic rubies ruined the market for real stones, and after many vicissitudes the Burma Ruby Mines company finally ceased operations in 1927. The system adopted was to excavate large open pits, from which the ruby bearing earth was removed and washed by machinery. The rubies occur in situ near the junction of gneissose and calcareous rocks, and some attempt was made at mining the solid rock, but the stones proved inferior to those naturally weathered out. The industry is still carried on by native workers and in addition to rubies, sap phires, spinels and other coloured stones are obtained. MogOk is also used to a small extent as a hill station.