Akaogiite
Akaogiite is an exceedingly rare mineral, one of natural forms of titanium dioxide. It is the high-pressure polymorph of TiO2, polymorphous with anatase, brookite and another high-pressure phase called "TiO2 II".
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Wikipedia
Akaogiite is an exceedingly rare mineral, one of natural forms of titanium dioxide. It is the high-pressure polymorph of TiO2, polymorphous with anatase, brookite and another high-pressure phase called "TiO2 II".