H2O polymorphs

Ice VI

Mineral name: unnamed

Discovery: Democratic Republic of Congo (diamond inclusion) 

＊References＊

• Kagi H., Lu R., Davidson P., Goncharov A. F., Mao H. K., and Hemley R. J. 2000. Mineralogical Magazine 64:1089–1097. (Discovery based on infrared spectoscopy)

Ice VII

Mineral name:  Ice-VII

Discovery:  Orapa, Namaqualand, Southern Africa, Cullinan mine, Gauteng province, South Africa (diamond inclusions) 

＊References＊

• Tschauner O., Huang S., Greenberg E., Prakapenka V. B., Ma C., Rossman G. R., Shen A. H., Zhang D., Newville M., Lanzirotti A., and Tait K. 2018. Science 359:1136–1139. (Discovery)