Burma, jade, gems

Describes maw-sit-sit, a distinctive bright to dark green ornamental rock from northern Burma (Myanmar), occurring near the jadeite deposits of the Hpakan region. Gübelin examines its appearance, gemological properties, texture and mineralogical composition, distinguishing it from jadeite jade and other green ornamental materials. The material is characterized by an intimate mixture of contrasting green and dark minerals that produces its characteristic mottled appearance. Microscopic and mineralogical observations demonstrate that maw-sit-sit is not a single mineral but a complex rock composed of several constituents. The article documents its occurrence, properties and identification and represents one of the earliest detailed gemological descriptions of this unusual Burmese gem material. Also contains brief mention of the Naniazeik ruby/spinel mines.