The alleged story of the Dropa Stones is as follows. In 1938, an archeological expedition was sent to investigate a secluded area of the Baian-Kara-Ula Mountains on the border that divides China and Tibet. The group discovered a series of caves at the summit of the mountains. The caves contained a large collection of graves and the walls were decorated with drawings of people with elongated heads together with images of the sun, moon, and stars. The archeologists uncovered the graves and discovered the remains of ancient beings. The skeletons were a little more than three feet tall, with abnormally large skulls. Inside of the tombs a collection of stone disks were recovered. The disks were almost twelve inches in diameter, with a hole in the center. The objects had a groove on the surface of the disk and spiraled outwards from the center hole forming a double spiral. Closer inspection showed that the grooves were actually a line of small carvings or signs.
The disks were labeled the Dropa Stones. Subsequent investigations have found a total of 716 Dropa Stones in the Baian-Kara-Ula Mountain caves. The Dropa Stones were sent to a variety of scholars for investigation. One of them, Professor Tsum Um Nui of the Beijing Academy for Ancient Studies, found that the spiral grooves were actually a line of characters written in an unknown language. In 1962, he announced that he had managed to translate the language. For a long time, the Peking Academy of Prehistory forbade the professor from publishing anything about the Dropa Stones. However, after many years of debate he published his hypothesis.
Tsum Um Nui claims that an alien spacecraft crashed in the Bayan Har Shan region 12,000 years ago. The occupants were aliens called Dropa or Dzopa. The Dropa could not repair their craft, so they tried to adapt to the conditions on Earth. Meanwhile, the local Ham tribesmen hunted down and killed most of the aliens. Supposedly, the aliens had intermarried with the locals, making identification of the origins of the skeletons more difficult. Many people have challenged these claims and Tsum Um Nui was forced to resign from the Beijing Academy. The Dropa Stones have been disappearing all over the world and are not available for public viewing at any museum. However, pictures of the artifacts do exist.