Orpiment As

The orpiment structure is found also in the selenide As2Se3. 

Calculations of the density of valence states in AS2S3, As2Se3 and As2Te3 have recently been reported [905]. 

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Each of these elements occurs naturally as a sulphide ore arsenic as realgar As S,, orpiment As, Sg and arsenical pyrites with approximate formula FeAsS antimony as stibnite Sb2S3 and bismuth as B12S3. 

The chief minerals of arsenic include orpiment, As S (from Latin anripigmentum, yellow pigment), realgar, AsS (a red substance), arseno-lite, As Op, and arsenopyrite, FeAsS. Arsenic trioxide (arsenious oxide) is obtained by roasting ores of arsenic. The element is made by reducing the trioxide with carbon or by heating arsenopyrite ... 

Monoclinic crystals, the fracture of which has a fat-like lustre.The powder of realgar is orange. Specific gravity 3 3 9 melting point 308 320°C, boiling point 565 C. It makes a transition from ci(red) to g(black) at 267 0. dL has a specific gravity of 3 506 and 3 3 25 The heat of formation amounts 0.3 kcal per mol. It is slowly oridized by the air especially in the sun producing orpiment, As Sj, and arsenious acid,... 

The name of this elixir can also be rendered as Cinnabar Flower, where flower denotes the sublimate and cinnabar is its color as said below, the elixir sometimes will be of a vivid scarlet color like cinnabar. The Taiqing jinye shendan jing, i.iyb-ihb, describes a similar method where cinnabar is refined with realgar and orpiment as the Mysterious and Yellow does in the methods of the Nine Elixirs, these two minerals incorporate Yin and Yang in the crucible. For another translation of this section of the Nine Elixirs see Ware, Alchemy, Medicine and Religion in the China of a.d. 320, 78-79. 

Arsenic sulfides were known in antiquity. Pliny described how orpiment (As Sj) was won in mines. Mortality was high among the slave workers who handled the substance. The situation was especially dangerous for those who had to treat minerals containing orpiment and prepare arsenic oxide. 

Realgar AsS is a red mineral, orpiment As S a yellow mineral, often associated with each other, and found as deposits near hot springs and as a subhmates from volcanoes (see Figure M71). 

Early known uses of orpiment as a pigment occur in Middle and New Kingdom Egypt (sixteenth to eleventh centuries BC) as painted decoration on wooden coffins and stelae and as a cosmetic (Colinart, 2001). Because of its bright colour, the pigment was popular for use on mediaeval manuscripts and it has been identified from the Book of Kells (Meehan, 1994). Derbyshire and WithnaU (1999) have identified orpiment on Elizabethan miniatures. FitzHu (1997) reviews the widespread use of orpiment in western and eastern art until the end of the nineteenth century, when it was largely phased out due to its toxicity. 

Carlyle (2001) lists a number of nineteenth century British terms indicating shade and/or soiuce variants of vermilion including Chinese v., carmine v., European v., pale v. deep v. and (Field s) orange v. as well as scarlet v. and extract of v. Typical adulterants of the period are given by Salter (1869) and Standage (1887) these include brickdust and orpiment as well as iron oxide, Persian red and iodine scarlet (qq.vl). Toch (1916) describes permanent v. as well as American quicksilver v. and Trieste v., the latter so called because it was foimd and made in the region. 

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