SULPHUR LUMPS

Pure Sulfur is bright yellow. The color may be altered if impurities are present. Clay and selenium impurities, as well as volcanic mixtures in sulfur can cause it to be slightly red, green, brown, or gray. Sulfur often occurs in petroleum deposits, where it is found coated with greasy black petroleum. Sulfur crystallizes in the orthorhombic system, but an uncommon monoclinic form of sulfur also exists. This monoclinic form is scientifically considered a different mineral than Sulfur, and is scientific name is Rosickyite. Most dealers selling Rosickyite usually label the mineral as "Monoclinic Sulfur". Sulfur is soft, light in weight, and very brittle. Therefore, care must be exercised when handling and storing specimens. When kept moist or not allowed to dry when wet, hydrogen will mix with the Sulfur, forming hydrogen sulfide (H2S), which causes the deterioration of a specimen. To prevent this, Sulfur should not be stored under humid conditions. (See Storing minerals for more information). It is best not to wash Sulfur specimens, as warm water will dissolve it. Sulfur also the tendency to crack when exposed to even mild heat, including body heat. It must be handled as little as possible, and kept out of light to avoid it from cracking.