Common. Abundant in massive form (granular or powdery crusts) in the first oxidation zone and particularly so in the upper levels. In the second oxidation zone as rare, but well-formed crystals.
- 1st Oxidation Zone
- 2nd Oxidation Zone
Doubly terminated prismatic crystals with stepped faces were found in the second oxidation zone in 1973, almost certainly on 28 Level (Key, 1977). Green, twinned, tabular, pseudo-hexagonal plates of bayldonite were found in the second oxidation zone in 1980. Pseudo-rhombohedral crystal are also noted (Von Bezing et al., 2014).
Paragenetic and General Notes
Bayldonite has been reported to form pseudomorphs after the following minerals: azurite (rare); dolomite (rare); mimetite (common); tennantite (rare); wulfenite (rare).
The following minerals have been reported to form pseudomorphs after bayldonite: olivenite (rare).
It should be noted that a majority of "bayldonite after mimetite" pseudomorphs from the
first oxidation zone turn out, on analysis, to be arsentsumebite after