Sulfur (spelled Sulphur in some countries) is an element and a mineral; as an element it meets the criteria of a mineral. Also known as a native element (native; found in a chemically uncombined state). Crystallized Sulfur is a striking mineral with its unmistakable bright yellow color and vitreous luster. It is found associated with numerous contrasting minerals, including Calcite, Celestine, Gypsum, Barite, and Quartz. Note: Sulfur does not have an unpleasant smell; when water (including high humidity) mixes with it, a very small amount of hydrogen sulfide gas is emitted, creating that “rotten egg” smell. Just keep it dry!
Its crystal system is orthorhombic, often forming dipyramidal and tabular crystals. Other forms include granular, encrusting, stalactitic, hopper and massive.
Sulfur is a common mineral, in fact, it is the fifth most common on Earth; though found in native form, it usually occurs as sulfide (e.g., Pyrite) and sulfate (e.g., Gypsum) minerals. However, quality specimens occur in limited localities, including Bolivia, Italy, Poland, Russia and Spain.