acicular
alkali-beryl
botryoidal
hexagonal
multi-terminated
pinacoid
pseudomorph
tabular
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Glossary: pseudomorph

A pseudomorph is a mineral that has taken on the form of another mineral. If mineral A has taken on the form of mineral B, we call that "A pseudomorph after B". This can happen when the chemical composition of mineral B changes into that of A, retaining (largely, or partly) the form of B. See for instance the first image.
Pyrite may, partially or wholly, chemically change into goethite while largely retaining pyrite's characteristic shape, forming "goethite pseudomorph after pyrite".
An assumed pseudomorph after pyrite, present within a vorobyevite habit.
Many pseudomorphs within vorobyevite from Deo Darrah are hexagonal.