Schneiderhöhnite

Schneiderhöhnite


Composition: Fe2+Fe3+3As3+5O13
Crystal System : Triclinic
Colours: Nearly black, dark brown
Lustre : Adamantine, metallic
Hardness (H) : 3
Specific Gravity (S.G) : 4.3
Year of Discovery: 1972
IMA Number: 1973-046
IMA Status: Approved
Discovered By: T.L. Kruger (Tsumeb geologist)
Named for: Hans Schneiderhöhn (German mineralogist)

Tsumeb is the Type Locality

Distribution

Very rare. Second oxidation zone.

Occurrence

  • Supergene
  • 2nd Oxidation Zone

Notable Finds

The mineral was discovered on 29 Level, in the second oxidation zone.

Paragenetic and General Notes

The type specimen of schneiderhöhnite occurs in chalcocite / tennantite ore, with stottite and leiteite.

As flattened, curved crystals, to 15 mm, with a single exceptional example of 30 mm, rarely terminated.  Also spindle-shaped crystals, in aggregates. Perfect cleavage on {100}, and the cleavage is usually prominent.

The middle portion of the second oxidation zone - levels 29 through 32 - has yielded several new minerals, including schneiderhöhnite (29 Level), leiteite (29 Level), reinerite (29 Level), stottite (30 Level), and ludlockite (probably 30 Level).  Cesbron et al. (1977) suggest that these minerals are all probably part of the same paragenesis. 

It is interesting to note that schneiderhöhnite, leiteite, ludlockite and reinerite are all arsenites - in which the arsenic occurs in its intermediate As(III) oxidation state. This is significant because it suggests that this paragenesis formed under relatively reducing conditions