Cinnabar
53464
224902618
2008-07-10T22:38:28Z
R. fiend
55767
{{for|the plant resin|Dragon's blood}}
{{for|the moth|Cinnabar moth}}
{{Infobox mineral
| name = Cinnabar
| category =
| boxwidth =
| boxbgcolor =
| image = Cinnabar.jpg
| imagesize =
| caption =
| formula = mercury(II) sulfide, HgS
| molweight =
| color = Brownish-red
| habit = Rhombohedral to tabular. Granular to massive
| system = [[Hexagonal]]
| twinning =
| cleavage = Prismatic, perfect
| fracture = Uneven to subconchoidal
| mohs = 2-2.5
| luster = Adamantine to dull
| refractive = 2.940-3.220<ref name=schumann>{{cite book
|author=Schumann, Walter
|title=Gemstones of the World
|place=New York
|publisher=Sterling
|year=1997
|isbn=0806994614}}</ref>
| opticalprop =
| birefringence =
| pleochroism =
| streak = Scarlet
| gravity = 8 - 8.2 g/cm³
| density =
| melt =
| fusibility =
| diagnostic =
| solubility = 3×10<sup>-26</sup> g per 100 ml water {{Fact|date=April 2007}}
| diaphaneity =
| other =
}}
'''Cinnabar''', sometimes written '''cinnabarite''', is a name applied to red [[mercury(II) sulfide]] ([[mercury (element)|Hg]][[sulfide|S]]), or native [[vermilion]], the common [[ore]] of [[mercury (element)|mercury]]. The name comes from the [[Greek language|Greek]] - "kinnabari" - used by [[Theophrastus]], and was probably applied to several distinct substances. Other sources say the word comes from the [[Persian language|Persian]] ''zinjifrah'', a word of uncertain origin. In Latin it was known as ''minium'', meaning also "red lead" - a word probably borrowed from [[Iberian language|Iberian]]<ref>''OED'' "minium".</ref> (cf. [[Basque language|Basque]] ''armineá'' "cinnabar").
==Structure==
HgS adopts two structures, i.e. it is [[dimorphous]].<ref>Wells, A.F. (1984). Structural Inorganic Chemistry, Oxford: Clarendon Press. ISBN 0-19-855370-6.</ref> The more stable form is cinnabar, which has a structure akin to that for [[mercury(II) oxide|HgO]]: each Hg center has two short Hg-S bonds (2.36 [[Å]]), and four longer Hg---S contacts (3.10, 3.10, 3.30, 3.30 Å). The black form of HgS has the [[zinc blende]] structure.
==Properties==
Cinnabar is generally found in a massive, granular or earthy form and is bright scarlet to brick-red in color. It occasionally occurs, however, in crystals with a non-metallic adamantine luster. Cinnabar has a rombohedral bravais lattice, and belongs to the hexagonal crystal system, trigonal division. Its crystals grow usually in a massive habit, though they are sometimes twinned. The twinning in cinnabar is distinctive and forms a penetration twin that is ridged with six ridges surrounding the point of a pyramid. It could be thought of as two scalahedral crystals grown together with one crystal going the opposite way of the other crystal. The [[Mohs scale of mineral hardness|hardness]] of cinnabar is 2 - 2.5, and its [[specific gravity]] 8.998.
Cinnabar resembles [[quartz]] in its symmetry and certain of its optical characteristics. Like quartz, it exhibits [[birefringence]]. It has the highest [[refraction|refractive]] power of any [[mineral]]. Its mean [[Refractive index|index]] for [[sodium]] light is 3.08<ref name=schumann/>, whereas the index for diamond—a substance of remarkable refraction— is 2.42 and that for GaAs is 3.93. <br>
See [[List of indices of refraction]].
[[Image:cinnabar09.jpg|thumb|right|250px|Cinnabar Mercury ore from Nevada, USA]]
==Occurrence==
Generally cinnabar occurs as a vein-filling [[mineral]] associated with recent [[Volcanism|volcanic activity]] and alkaline [[hot spring]]s.
Cinnabar is found in all localities that yield mercury, notably [[Almadén]] ([[Spain]]); [[New Almaden]] ([[California]]); [[Hastings Mine]] and [[St. John's Mine]], [[Vallejo, California]];<ref>C.Michael Hogan, Marc Papineau et al., ''[[Environmental Assessment]] of the columbus Parkway Widening between Ascot Parkway and the Northgate Development, Vallejo'', Earth Metrics Inc. Report 7853, California State Clearinghouse, Sept, 1989</ref> [[Idrija]] ([[Slovenia]]); [[New Idria, California|New Idria]] ([[California]]); [[Landsberg, Rhineland-Palatinate|Landsberg]], near [[Obermoschel]] in the [[Rhineland-Palatinate|Palatinate]]; [[Ripa]], at the foot of the [[Apuan Alps]] ([[Tuscany]]); the mountain Avala (Serbia); [[Huancavelica]] ([[Peru]]);Murfreesboro, Arkansas [[Terlingua, Texas|Terlingua]] ([[Texas]]); and the province of [[Guizhou]] in [[China]], where fine crystals have been obtained.
Cinnabar is still being deposited at the present day from the hot waters of [[Sulphur Bank]], in California, and [[Steamboat Springs, Nevada]].
==Mining and extraction of mercury==
[[Image:cinnab1.jpg|thumb|left|Cinnabar crystals on [[dolomite]] from China.]]
Cinnabar was mined by the [[Roman Empire]] both as a pigment (Vitruvius, DA VII; IV-V) (Pliny, HN; XXXIII, XXXVI-XLII) and for its mercury content (Pliny HN; XXXIII, XLI), and it has been the main source of mercury throughout the centuries. Some mines used by the Romans remain active today. {{Fact|date=September 2007}}
To produce liquid (quicksilver) mercury, crushed cinnabar ore is roasted in rotary furnaces. Pure mercury separates from sulfur in this process and easily evaporates. A condensing column is used to collect the liquid mercury, which is most often shipped in iron flasks.
Because of the high toxicity of mercury, both the mining of cinnabar and refining for mercury are hazardous and historic causes of [[mercury poisoning]]. In particular, the Romans used convict labor in their mines as a form of death sentence. The Spanish also used shorter term convict labor at the [[Almadén]] mines, with a 24% overall fatality rate in one 30 year period.
Abandoned mercury mine processing sites often contain very hazardous waste piles of roasted cinnabar calcines. Water runoff from such sites is a recognized source of ecological damage.
==Medicinal use==
Much fuss is made about medicinal use of Cinnabar, however Cinnabar has been used over the ages medicinally in the East and the West and its side effects are long known.
It is known to be highly [[Toxicity|toxic]][http://physchem.ox.ac.uk/MSDS/ME/mercuric_sulphide.html] - perhaps the first record of this is in the [[Ben cao hui yan|Thoroughly Revised Materia Medica]] (1751) and later in the work [[Ben cau hai li|Harm and Benefit in the Materia Medica]] (1893). It is nevertheless used today (as is [[arsenic]]) to treat certain types of conditions with Western Medical Science translations approximating somewhere between "insomnia" and "depression". It is not "using poison to cure poison", as some claim - such images should be viewed as curious observation, not an offering for a mechanism of operation.
Modern herbal extracts that contain cinnabar (zhū shā / 朱沙) should be that obtained after [[aqueous tituration]] to refine the Cinnabar (HgS) away from any Mercury Oxide (HgO), as it is the water- and gastric-soluble forms of Mercury which are responsible for its toxicity<ref>{{Citation
| last1 = Bensky | first1 = Dan
| last2 = Clavey | first2 = Steven
| last3 = Stöger | first3 = Erich
| title = [[Materia Medica: 3rd Edition]]
| publisher = [[Eastland Press]]
| year = 2004
| pages = 1045-1047
| isbn = 0-939616-4-24}}</ref>. The result is called "Floating Cinnabar" (shuǐ fēi zhū shā / 水飛朱沙), as opposed to líng shā (靈沙 / lit. "divine sand") or the highly toxic chén shā (辰沙 or 陳沙; lit "[[Chen (state)|Chen]] sand"). The ''Harm and Benefit in the Materia Medica'' notes:
<blockquote>"...should be used unprepared. ... If refined with fire it is toxic, and taking it has often been fatal."</blockquote>
In Bensky, Clavey & Stöger's ''Materia Medica'''s entry for it, conveniently located at the beginning of the "Obsolete Substances" section, you will see this expressed in the modern language of chemistry:
<blockquote>"...completely pure cinnabar (HgS), when heated in the presence of oxygen, turns into mercury oxide (HgO), which is soluble in diluted acids such as gastric acid."</blockquote>
==Decorative use==
Cinnabar has been used for its color in the new world since the [[Olmec]] culture<ref>''New World's Oldest'', in Time Magazine, Monday, Jul. 29, 1957[http://www.time.com/time/magazine/article/0,9171,825208,00.html]</ref>. Cinnabar was often used in royal burial chambers during the peak of Mayan civilization. The red stone was inserted into limestone sarcophagi, both as a decoration and, more importantly, to deter vandals and thieves with its well-known toxicity.{{Fact|date=February 2007}}
The most popularly known use of cinnabar is in Chinese carved [[lacquerware]], a technique that apparently originated in the [[Song Dynasty]][http://www.askasia.org/teachers/images/image.php?no=659]. The danger of mercury poisoning may be reduced in ancient lacquerware by entraining the powdered pigment in [[lacquer]][http://www.cst.cmich.edu/users/dietr1rv/cinnabar.htm], but could still pose an [[environmental hazard]] if the pieces were accidentally destroyed. In the modern jewelry industry, the toxic pigment is replaced by a resin-based [[polymer]][http://en.mimi.hu/jewelry/cinnabar.html] that approximates the appearance of pigmented lacquer.
In the [[Byzantine Empire]], the [[Emperor]] and certain [[privilege]]d [[bishop]]s (such as the [[Ecumenical Patriarch]] and the [[Archbishop of Cyprus]]) were allowed the exclusive right of signing their names with ink colored [[vermilion]] by the addition of cinnabar.
==Other forms of cinnabar==
*'''Hepatic cinnabar''' is an impure variety from the mines of [[Idrija]] in the [[Carniola]] region of [[Slovenia]], in which the cinnabar is mixed with [[bitumen|bituminous]] and earthy matter.
*'''Metacinnabarite''' is a black-colored form of HgS, which crystallizes in the cubic form.
*'''Synthetic cinnabar''' is produced by treatment of Hg(II) salts with [[hydrogen sulfide]] to precipitate black, synthetic metacinnabarite, which is then heated in water. This conversion is promoted by the presence of [[sodium sulfide]].<ref>Holleman, A. F.; Wiberg, E. "Inorganic Chemistry" Academic Press: San Diego, 2001. ISBN 0-12-352651-5.</ref>
*'''Hypercinnabar''', crystallise in the hexagonal form.
==References==
<references/>
==External links==
*[http://physchem.ox.ac.uk/MSDS/ME/mercuric_sulphide.html MSDS for cinnabar]
*[http://www.dartmouth.edu/~toxmetal/TXSHhg.shtml Dartmouth Toxic Metals Research Program - Mercury]
*[http://www.galleries.com/minerals/sulfides/cinnabar/cinnabar.htm Cinnabar visual reference]
== See also ==
*[[China red]]
*[[List of minerals]]
[[Category:Sulfide minerals]]
[[Category:Mercury minerals]]
[[Category:Traditional Chinese medicine]]
[[Category:Alchemical substances]]
[[bs:Cinabarit]]
[[bg:Цинобър]]
[[ca:Cinabri]]
[[cs:Cinabarit]]
[[da:Cinnober]]
[[de:Cinnabarit]]
[[et:Kinaver]]
[[es:Cinabrio]]
[[eu:Zinabrio]]
[[fr:Cinabre]]
[[gl:Cinabrio]]
[[it:Cinabro]]
[[he:צינובר]]
[[lv:Cinobrs]]
[[lt:Cinoberis (mineralas)]]
[[hu:Cinnabarit]]
[[nl:Cinnaber]]
[[ja:辰砂]]
[[no:Sinober (mineral)]]
[[nds:Cinnabarit]]
[[pl:Cynober (minerał)]]
[[pt:Cinábrio]]
[[ru:Киноварь]]
[[simple:Cinnabar]]
[[sk:Cinabarit]]
[[sl:Cinabarit]]
[[fi:Sinooperi]]
[[vi:Chu sa]]
[[tr:Zincifre]]
[[uk:Кіновар]]
[[zh:朱砂]]