Masutomilite is a rare, little-described mineral from the micas group.
You can see masutomylite stone for sale and buy it in the Minerals of Russia online store.
Physical properties of Masutomilite
Formula: (K,Rb)(Li,Mn3+,Al)3(AlSi3O10)(F,OH)2
Colour: Pale purplish-pink
Hardness: 2½
Specific Gravity: 2.90 - 2.94
Crystal System: Monoclinic
Member of: Trioctahedral mica Group > Mica Group