Amber calomel crystals and bright yellow terlinguaite on gossan matrix, 3 mm. across
General
Category
Halide mineral
Formula (repeating unit)
(Hg2)2+Cl2
IMA symbol
Clo[1]
Strunz classification
3.AA.30
Crystal system
Tetragonal
Crystal class
Ditetragonal dipyramidal 4/mmm (4/m 2/m 2/m) -
Unit cell
a = 4.4795(5) Å, c = 10.9054(9) Å; Z=4
Identification
Color
Colorless, white, grayish, yellowish white, yellowish grey to ash-grey, brown
Crystal habit
Crystals commonly tabular to prismatic, equant pyramidal; common as drusy crusts,
earthy, massive.
Twinning
Contact and penetration twins on {112}
Cleavage
Good on {110}, uneven to imperfect on {011}
Fracture
Conchoidal
Tenacity
Sectile
Mohs scale hardness
1.5
Luster
Adamantine
Diaphaneity
Transparent to translucent
Specific gravity
7.5
Optical properties
Uniaxial (+); very high relief
Refractive index
nω = 1.973 nε = 2.656
Birefringence
δ = 0.683
Pleochroism
Weak, E > O
Ultraviolet fluorescence
Brick-red under UV
References
[2][3][4]
Calomel is a mercury chloride mineral with formula Hg2Cl2 (see mercury(I) chloride). It was used as a medicine from the 16th to early 20th century, despite frequently causing mercury poisoning in patients.[5]
The name derives from Greek kalos (beautiful) and melas (black) because it turns black on reaction with ammonia. This was known to alchemists.[3]
Calomel occurs as a secondary mineral which forms as an alteration product in mercury deposits. It occurs with native mercury, amalgam, cinnabar, mercurian tetrahedrite, eglestonite, terlinguaite, montroydite, kleinite, moschelite, kadyrelite, kuzminite, chursinite, kelyanite, calcite, limonite and various clay minerals.[2]
The type locality is Moschellandsburg, Alsenz-Obermoschel, Rhineland-Palatinate, Germany.[3]
^Davis, L. E (2000-07-01). "Unregulated potions still cause mercury poisoning". Western Journal of Medicine. 173 (1): 19. doi:10.1136/ewjm.173.1.19. PMC 1070962. PMID 10903282.
Calomel is a mercury chloride mineral with formula Hg2Cl2 (see mercury(I) chloride). It was used as a medicine from the 16th to early 20th century, despite...
The saturated calomel electrode (SCE) is a reference electrode based on the reaction between elemental mercury and mercury(I) chloride. It has been widely...
administration of calomel. In 1862 a soldier in the American civil war, Carleton Burgan, suffered a similar disfigurement when he was treated with calomel for an...
Retrieved 6 February 2023. "Awstats: static generated reports of web logs". CALOMEL. 2012-03-21. Archived from the original on 2015-03-17. Retrieved 2015-02-12...
electrode. Reference electrodes generally used are hydrogen electrodes, calomel electrodes, and silver chloride electrodes. The indicator electrode forms...
epiglottitis complicated by the treatments, including multiple doses of calomel, a purgative, and extensive bloodletting which likely caused hypovolemic...
Society, London, 1958. See: Winckler, F. L. (1831) "Ueber die Zersetzung des Calomels durch Bittermandelwasser, und einige Beiträge zur genaueren Kenntniss der...
membrane reference electrode, typically a silver chloride electrode or calomel electrode are required on each side of the membrane. Their purpose is to...
chemists Joseph Louis Gay-Lussac and Louis Jacques Thénard by heating calomel (Hg2Cl2) with phosphorus. Later during the same year, the English chemist...
solution. The reference electrode may be a silver chloride electrode or a calomel electrode, and the hydrogen-ion selective electrode is a standard hydrogen...
Acorus calamus (also called sweet flag, sway or muskrat root, among many other common names) is a species of flowering plant with psychoactive chemicals...
was attributed to the formation of Hg-Cl compounds (e.g., corderoite, calomel, and terlinguaite) and calcium sulfate, gypsum. As the mercury cell as...
On the Style" 3768. "Kitty Clyde" 3769. "Three Leaved Shamrock" 3770. "Calomel" 3771. "The Old Bachelor", "The Crookery Maid" 3772. "Skye Boat Song" 3773...
recovery was overwhelmed by his doctors, who treated him with "ipecac, calomel, opium, and quinine" at 40 grains per dose (approximately 2.6 grams), and...
mercury. It features a Hg(II) centre. Mersalyl was originally adapted from calomel (Hg2Cl2), a diuretic discovered by Paracelsus. Thiomersal – Organomercury...
(2021). "Pigments — Mercury-based red (cinnabar-vermilion) and white (calomel) and their degradation products". Archaeological and Anthropological Sciences...
Philadelphia yellow fever epidemic, Rush treated patients with bleeding, calomel, and other early medicinal techniques that often were ineffective and actually...
doctor's equipment consisted of a saw and a gallon of whisky and a satchel of calomel...." Flags in the Dust (New York: Vintage Books, 1973), pp. 94-95. Faulkner...
highly toxic heavy metal mercury, referred to as cinnabar, quicksilver or calomel, was administered as an ointment or pill or inhaled as a vapor to treat...
Civil War service, Alcott contracted typhoid fever and was treated with calomel, a compound containing mercury. Recent analysis of Alcott's illness suggests...
measurements. For environmental reasons it has widely replaced the saturated calomel electrode. For example, it is usually the internal reference electrode...
aspirin, sometimes I take a calomel. Wagstaff: Say, I'd walk a mile for a calomel. Baravelli: You mean chocolate calomel? I like-a that too, but you no...
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