5 - 6

Actinolite
Apatite
Augite
Arsenopyrite
Babingtonite
Bustamite
Chromite
Diopside
Enstatite
Franklinite
Hedenbergite
Hematite
Hypersthene
Johannsenite
Loellingite
Magnesiochromite
Magnetite
Omphacite
Opal
Pitchblende (Uraninite)
Pyroxmangite
Rammelsbergite
Rhodonite
Safflorite
Serandite
Tephroite
Tremolite
Uraninite

Many more to come soon!