It was named in honor of Thomas Geiger (1886–1976), Wiesendangen, Switzerland, who studied the Falotta manganese ores.
[4] The chemical composition was found by using an electron microprobe in the Falotta mines in Switzerland.
It is mainly found in cavities in adiolarites, which are a form of igneous rock that have either a radial or fanlike texture of crystals.
Nero Mine, Borghetto Di Vara, La Spieza, Italy.
Minerals within this group have a formula where M equals either copper, calcium, manganese, zinc, or cobalt.