When doped with potassium hexafluoromanganate(IV) (K2[MnF6], with Mn4+) it forms a narrow band red producing phosphor, (often abbreviated PSF or KSF), of economic interest due to its applicability in LED lighting and displays.

Occurs naturally as hiereatite, found in the Aeolian islands (Sicily, Italy).

[3] A hexagonal form demartinite has also been found at the rim of volcanic fumaroles in the same islands.

[1] When doped with potassium hexafluoromanganate(IV) (K2[MnF6]), a narrow band red phosphor is produced, emitting at around 630 nm.

This substance has application improving the white light quality of white LEDs that use a blue emitting LED in combination with the yellow cerium doped yttrium aluminium garnet phosphor (YAG), Y3Al5O12:Ce3+.