蒙陰金剛石礦
Shandong, China
山東蒙陰是中國第一個原生(金伯利岩型)金剛石礦床,歷史上為全國最重要的鑽石產地之一。
China's first kimberlite diamond deposit
The Mengyin district in central Shandong hosts diamond-bearing kimberlite pipes and was the first primary (in-rock) diamond source developed in China, beginning in the 1960s. It remains one of the country's principal diamond localities, with the diamonds carried up from the deep mantle in Mesozoic kimberlite intrusions.
What Mengyin is known for
- Diamond — octahedral and dodecahedral crystals from kimberlite
- Associated kimberlite indicator minerals (pyrope garnet, olivine)
Availability
Most Mengyin production is industrial, and gem-quality or well-formed crystal specimens are rare. Mengyin's significance for collectors is primarily as the historic cradle of Chinese diamond mining rather than as a steady source of display crystals.
The Changma kimberlite district
China's first primary (in-rock) diamonds were found in 1965, and the Mengyin field — the Changmazhuang, Xiyu, and Poli kimberlite belts — became the country's first developed kimberlite diamond source. The 701 Changma mine, working the Shengli (“Victory”) No. 1 pipe, has been the principal producer, yielding on the order of several thousand carats a year, a minority of it gem quality. Most output is industrial, which is why loose collector crystals are scarce.