INTRODUCTION In the summer of the year 1927 instructions were given Mr. C. C. Sun and myself, geologists of the Sino-Swedish Research Association in Taiyuanfu, by Dr. E. T. Nystrom, Director of that Association, to proceed to South Shansi and there undertake a general survey of the geology and mineral resources. Special instructions were given to visit the P'ing Lu Gypsum deposits (平陸石膏礦) which are situated at the southern frontier of Shansi