Moissanites of the Popigai Astrobleme     

S. A. Gromilov  V. P. Afanasiev  N. P. Pokhilenko 《Doklady Earth Sciences》2018,481(2):997-999

Moissanites were found in tagamites of the Popigai meteorite crater along with impact diamonds. We have studied 55 samples including 49 individual polytypes and six intergrowths. The numbers of 6H, 15R, 4H, 6H/15R, and 6H/4H polytypes are 82, 7, 5, 4, and 2%, respectively. By the assemblage of polytypes, the moissanites of the Popigai astrobleme are distinct from kimberlite moissanites, as well as from synthetic SiC, which is characterized by the absence of the 4H polytype and the presence of more diverse inclusions (including Fe-bearing). The Popigai astrobleme is one of few objects with reliable natural moissanite. Technogenic contamination is excluded, since any researcher can find this mineral in tagamites.  相似文献   

Synthesis of New Polytypic Modifications of Fe7C3 at 5.5 GPa     

Chepurov  A. I.  Gromilov  S. A.  Sonin  V. M.  Zhimulev  E. I.  Sukhikh  A. S.  Chepurov  A. A.  Sobolev  N. V. 《Doklady Earth Sciences》2019,487(2):957-959

Doklady Earth Sciences - The results of experimental synthesis of carbide Fe7C3 at 5.5 GPa are presented. It is found that carbide Fe3C and several polytypes of carbide Fe7C3 are formed along with...  相似文献