Exceptions are ammoniojarosite and destinezite (nearly insoluble); gypsum (slightly soluble); and slavikite (slowly soluble with decomposition).
Ammoniojarosite is common as crusts and aggregates of yellow to red-brown crystals (rhombohedron and pinacoid, or pseudocubic rhombohedron) to about 0.
The mineral shows good cleavage normal to plates, and is found associated with magnesian apjohnite and epsomite, and sometimes with slavikite, ammoniojarosite, tschermigite, levinsonite-(Y), or zugshunstite-(Ce).
It is fairly widespread, but very sparse, occurring mostly on rock surfaces with ammoniojarosite.
There is nothing unusual about the geochemistry of this locality; if this explanation is valid, then ammoniojarosite may be more common than is recognized, and with its low solubility, it may prove to be an important unrecognized reservoir of nitrogen in low-pH soils.