Flowers of sulphur

 

These are delicate, needle-like yellow sulphur crystals. Sulphur crystals form when native sulphur solidifies from either molten sulphur cooling or when sulphur vapor condenses directly into solid form (sublimation). They occur where sulphur-rich gases escape from fumaroles, allowing the sulphur to crystallise as it cools. The distinctive yellow color comes from the elemental sulphur itself, while the needle or hair-like crystal structure (sometimes called “flowers of sulphur”) results from rapid crystallisation under specific temperature and pressure conditions.