Orpiment is a rare mineral and is known for its striking bright yellow color, though it can also be golden to brownish-yellow. With its yellow color, pearly luster and typical association with bright red Realgar, it forms a very aesthetic and colorful mineral combination. In addition to Realgar, other associations include Barite, Calcite, Quartz and Pyrite. Though this unique mineral contains a significant amount of arsenic, it need not be feared or disregarded as a collectable mineral; rather, one should simply wash their hands following handling (this should be a normal practice when handling any and all minerals and rocks).
The crystal system for Orpiment is monoclinic. Crystal formations are rare as it typically forms in foliated masses and crusts. Other forms include druzy, botyroidal, micaceous and in veins.
Orpiment specimens are found in limited localities, including China, France, Peru, Russia and the USA (Nevada, Utah).