Orpiment is a common monoclinic arsenic sulfide mineral. It has a Mohs hardness of 1.5 to 2 and a specific gravity of 3.49. It melts at 300 °C (570 °F) to 325 °C (620 °F). Optically, it is biaxial (−) with refractive indices of a = 2.4, b = 2.81, g = 3.02.

Orpiment is an arsenic sulfide mineral that crystallizes in the form of masses, botryoidal, and small prismatic shards (extremely rare). Its color is bright yellow to pale yellow, and forms from the decay of a mineral called Realgar, near volcanic steam holes or natural hot springs.

2023年9月5日 · Orpiment is a rare mineral composed of arsenic trisulfide, with the chemical formula As2S3. It is known for its distinctive bright yellow to orange-yellow color and has been used as a pigment in painting and for various purposes throughout history.

In low-temperature hydrothermal veins, hot springs and fumaroles; also commonly as an alteration product of arsenic minerals, especially realgar. 2.FA. Heated in a closed tube it fuses, volatizes and gives a dark yellow sublimate. Soluble in aqua regia and caustic alkalies. Contains arsenic - always wash hands after handling.

2024年12月17日 · Orpiment, a mineral with a rich history and unique properties, continues to captivate scientists, historians, and collectors alike. Its vibrant yellow hue, due to arsenic content, made it a prized pigment in ancient art and manuscripts.

Orpiment is often associated with bright red Realgar, and may form in strikingly colored and unique mineral combinations. Orpiment is a photosensitive mineral and will eventually dull and develop a white powdery film upon prolonged exposure to light.

orpiment, the transparent yellow mineral arsenic sulfide (As 2 S 3), formed as a hot-springs deposit, an alteration product (especially from realgar), or as a low-temperature product in hydrothermal veins. It is found in Copalnic, Romania; Andreas-Berg, Ger.; Valais, Switz.; and Çölemerik, Tur.

2020年10月5日 · Orpiment is a mineral that contains arsenic sulfide and crystallizes either as masses, botryoidal, and tiny prismatic shards. It develops near volcanic steam holes or hot springs and gets its bright yellow to pale yellow color from the decay of the mineral realgar.

14 小时之前 · “ A wonderful miniature sized specimen from the Twin Creeks Mine featuring very rare and fine quality deep blood red colored getchellite in the form of vitreous, platy crystal faces, with associated gemmy orange orpiment overgrowing silvery-grey stibnite. The largest orpiment measures about 1.2 cm.

Brief description of Orpiment: A rich lemon or canary yellow with fair covering power and good chemical stability. It's an arsenic sulfide which naturally occurs widely, but in relatively small deposits.