Witherite


Composition:

BaCO3

Crystal System : Orthorhombic
Colours: Colourless, white, grey, yellow
Lustre : Vitreous, resinous
Hardness (H) : 3.0-3.5
Specific Gravity (S.G) : 4.29
References: Strunz et al. (1958a)

 

Distribution

Very rare. Second oxidation zone. Questionable status at Tsumeb (Gebhard, 1999).

Occurrence

  • Supergene
  • 2nd Oxidation Zone

Paragenetic and General Notes

The occurrence of witherite was first recorded by Strunz et al. (1958a), who simply noted its presence in the second oxidation zone.  Strunz and Tennyson (1967) alluded to its rarity.  

Pinch and Wilson (1977) noted that witherite "forms milky grayish masses and minute white to cream-colored crystals of flat pseudo-hexagonal dipyramidal habit" and added that it is "found rarely in the lower oxidation zone."  

Lombaard et al. (1986) simply list witherite as "very rare".

Gebhard (1999), however, does not include witherite in his list of mineral species occurring at Tsumeb, and Von Bezing et al. (2007, 2016) note that Gebhard (op cit.) doubted the original identification.