The Mineral stibiconite

Stibiconite is an alteration mineral of Stibnite. It forms as a dull, crusty yellow replacement mineral over Stibnite. The pseudomorph is occasionally only partial, in which only a section of the crystal has been altered with the rest remaining intact. The name Stibiconite is derived from a combination of the Latin stibium, the old name for antimony, and konis, powder, alluding to this minerals powdery habit.