Ernstite

Ernstite was named on oxidized eosphorite. As eosphorite has by definition Mn2+ > Fe2+, then the ferric component could never be greater than 50 mole percent and is therefore only a named variety. Some of the water molecule occupancy in the empirical eosphorite formula may be converted to hydroxyl in the same ratio as the oxidized Fe. The above formula shows only hydroxyl plus oxygen in the formula instead of (OH, O, H20) as though oxygen and hydroxyl were in equivalent sites without any residual water in the structure. If the actual original material were a childrenite, it would be possible to have a ferric-dominant oxidized member of the series. No name has been proposed for oxidized childrenite, but any such new name would have to have ferric iron > 50 mole percent of the M site. Ernstite should be re-investigated.