Gray-crystalline non-metal, or a yellow colored powder m.p. 817 ºC (28 atm); 1503 ºF (28 atm) b.p. sublimes at 613 ºC; 1135.4 ºF density (yellow) 1.97 and (gray) 5.73 g/cc; (yellow) 122.98 and (gray) 357.71 pound/cubic foot	memory peg
	13th century, Albertus Magnus, Germany
	زرنيخ ([al-]zarnīkh) = gold-colored (Arabic)

Arsenic has been known since Antiquity in the form of its sulphides. Aristotle (384-322 BC) makes reference to sandarach and his student Theophrastus of Eresos (370-286 BC) named it arhenicum. The oxide known as White Arsenic is mentioned by the Greek alchemist Olympiodorus of Thebes (5th century AD), also obtained it by roasting Arsenic Sulphide.
Pliny, in his Historia Naturalis said:

"Sandarach is found in Gold and Silver mines. The redder it is, the more powerful its odour, the better its quality... Arsenicum is composed of the same matter as sandarach; the best in quality has the same color as that of the best gold, and that which is pale in color resembling sandarach is of inferior quality."

Yellow Orpiment and Realgar (Sandarach) (from: Pigments through the Ages)

"In [Pompeiupolis in Pontus] is Mt. Sandaracurgium ... which is hollowed out in consequence of the [arsenic] mining done there, since the workmen have excavated great cavities beneath it. The mine used to be worked by publicans who used as miners the slaves sold in the market because of their crimes; for, in addition to the painfulness of the work, they say that the air in the mines is both deadly and hard to endure on account of the grievous odor of the ore [red arsenic] so that the workmen are doomed to a quick death. What is more, the mine is often left idle because of the unprofitability of it, since the workmen are not only more than two hundred in number, but are continually spent by disease and death."

• White Arsenic (arsenic trioxide, As₂O₃).
• Yellow Arsenic (arsenic trisulphide, As₂S₃), (yellow) orpiment (> auripigmentum (Latin), = golden pigment), King's yellow.
• Red Arsenic (arsenic sulphide, AsS, As₂S₂), sandarach (Latin sandaraca, cf. Pers. sandarus, Skt. sindura), realgar (> rahj al ghar (Arabic) = powder of the mine), also named red orpiment, ruby arsenic, ruby sulphur.

Albertus Magnus (1193-1280) was the first to state that Arsenic contained a metal-like substance. In his book De Mineralibus he described obtaining the metal by heating orpiment with soap. However, his documentation is considered vague. In the Middle Ages, Arsenic received various names, such as Scherbenkobold, Napchenkobold, Goblet-fiend, Bowl-sprite, Cobaltu, etc.

It was not until 1649 that Johann Schröder (1600-1664) clearly reported the preparation of metallic Arsenic by reducing White Arsenic with charcoal. Thirty-four years later, Nicolas Lemery (1645-1715) also observed that metallic Arsenic was produced by heating White Arsenic with soap and potash.
This and all other metals were considered compounds until Antoine Lavoisier (1743-1794) established a new definition for elements.

Arsenic - Schneeberg
Native arsenic with calcite.
Schneeberg, Erzgebirge, Sachsen, Germany.
Specimen size 7 cm.

Photo by Thomas Witzke.

Arsenicum is from Arabic al-zarnīkh; this in turn is borrowed via Aramaic from Persian zarnik, "gold-colored" > zar = gold. It refers without any doubt to the golden colour of arsenic's chief ore: Yellow orpiment, which was well known as a dye-stuff by the ancients. The word zarnīkh or zirnikhi was borrowed by the Greeks and converted into αρσενικον [arsenikon]. This happened to sound very similar to αρρηνικον [arrènikon] = masculine, powerful (from αρρην, αρσην [arrèn, arsèn] = male). Due to this coincidence, it expressed the powerful properties of arsenic as a poison.
Αρσενικον became arsenicum in Latin, and came in most of the languages.

• Russian and other Slavic languages, Мышьяк, seems to be derived from мыш [myš] = mouse, perhaps it means "mouse poison".
• Arabian زرنيخ [zarnīkh], see above.
• New name New names
  Arsenon: According to The Atomic Elements: "Arsenon means heavenly to the 3.2 billion people in Asia in India, China and Japan. However, the word arsenic means, slimy and urine to them and that is why the name was changed."

• Mary Elvira Weeks, Discovery of the Elements, comp. rev. by Heny M. Leicester (Easton, Pa.: Journal of Chemical Education, 1968), pp. 92-95.
• Robert A. Nelson, Adept Alchemy III: The Philosophers' Stone, Arsenic & Gur Part One - Arsenic & Gur Part Two.
• Anil Aggrawal, Arsenic - The King of Poisons. Science Reporter, Febr. 1997. (on-line).