Title
karibibite
Composition
Fe3+2As3+4(O,OH)9
Crystal System
Orthorhombic
Status at Tsumeb
Confirmed
Abundance
Extremely rare
Distribution
Second and third (?) oxidation zones.
Paragenesis
Supergene.
Type Locality
No
Entry Type
Species TSNB189
General Notes
The first formal record of karibibite from Tsumeb is in the RRUFF Database (http://rruff.info/karibibite/display=default/R060380; accessed December 2015).
Karibibite from Tsumeb was first verified by analysis on specimens in Feinglos and Pinch collections, and in the collection of Chris Amo (Chris Amo, pers. comm. to M. Southwood, 2016). These specimens had originally been identified as ludlockite, with which the mineral is readily confused. Karibibite and ludlockite may appear similar in terms of colour and habit although at Tsumeb, karibibite tends to present with less ordered aggregates of poorly defined acicular crystals, with lower lustre and a more yellowish-orange colour than ludlockite.
According to Wilson (2022):
"Ludlockite in lesser quality specimens was later thought to occur as deep as the 3400 level, but much of that material, in smaller felted masses of a yellower color, proved to be karibibite instead."
A specimen of karibibite in the Southwood Collection (MS2016.065) has been verified by XRD and chalcocite and tennantite have been confirmed as matrix constituents for this specimen.
Associated Minerals
chalcocite; quartz; schneiderhöhnite; tennantite-(Zn)
