Halite

From Saltwiki
Jump to navigation Jump to search

Authors: Hans-Jürgen Schwarz, Nils Mainusch
English version by Christa Gerdwilker
back to Chloride


Halite[1][2][3] [4]
NaCl 27.4.2006-10x.JPG
Mineralogical name Halite
Chemical name Sodium chloride
Trivial name Common Salt, Rock Salt
Chemical formula NaCl
Other forms NaCl•2H2O (Hydrohalite)
Crystal system cubic
Crystal structure
Deliquescence humidity 20°C 75.4%
Solubility (g/l) at 20°C 6.135 mol/kg
Density (g/cm³) 2.163 g/cm3
Molar volume 27.02 cm3/mol
Molar weight 58.44 g/mol
Transparency transparent to translucent
Cleavage perfect
Crystal habit cubic crystal, granular, massive aggregates
Twinning none
Phase transition
Chemical behavior
Comments water soluble
Crystal Optics
Refractive Indices nD=1.5443
Birefringence
Optical Orientation isotropic
Pleochroism
Dispersion
Used Literature
[Steiger.etal:2014]Title: Weathering and Deterioration
Author: Steiger, Michael; Charola A. Elena; Sterflinger, Katja
Link to Google Scholar [Robie.etal:1978]Title: Thermodynamic properties of minerals and related substances at 298.15 K and 1 bar pressure and higher temperatures
Author: Robie R.A., Hemingway B.S.; Fisher J.A.
Link to Google Scholar [Dana:1951]Title: Dana's System of Mineralogy
Author: Dana J.D.
Link to Google Scholar


Abstract[edit]

Occurrence[edit]

Sodium chloride is obtained through mining or derived from the sea or salt lakes and is commonly used for cooking or as deicing salt for roads.
The sodium chloride content of sea water is around 2.7 M.%.

Origin of the halite found on monuments[edit]

Sodium chloride can enter buildings or monuments when these are in contact with materials containing this salt or even other salts containing either sodium or chloride, that might combine to produce NaCl in or efflorescence on them. Contamination with sodium and chloride ions can also occur through contact with salt laden ground or surface water. A range of cleaning materials (e.g., acidic and alkaline cleaners or combination of them), or previously used restoration materials (e.g., water glass) as well as Portland cement, can introduce sodium and chloride ions into monuments. Further common and important sources are deicing salts and maritime environments where the air and fogs may contain a significant amount of sodium chloride in suspension or dissolved in droplets.


Solubility behavior[edit]

The commonly occurring halite has a solubility of 6.13 mol/kg (20°C) and can be considered as a very soluble and, therefore, easily mobilized salt. Its solubility changes not significantly within a temperature range of 10 -30°C.

Figure 1: Solubility of sodium chloride in water. The molality m [n(NaCl)•kg(H2O)-1] is plotted versus the temperature.


Table 1: Solubility of halite at different round temperatures [according to [Steiger.etal:2008c]Title: An improved model incorporating Pitzer’s equations for calculation of thermodynamic properties of pore solutions implemented into an efficient program code
Author: Steiger, Michael; Kiekbusch, Jana; Nicolai, Andreas
Link to Google Scholar.
Temperature 10°C 20°C 30°C 40°C
Solubility [mol/kg] 6.11 6.13 6.17 6.22


Hygroscopicity[edit]

Figure 2: Deliquescence behaviour of sodium chloride. The water activity aw is plotted versus the temperature.

Halite has a deliquescence humidity of about 75% RH, therefore it tends to pick up moisture easily in most temperate climates.


Table 2: Deliquescence humidities of sodium chloride at different round temperatures [Steiger etal: 2014]Title: Weathering and Deterioration
Author: Steiger, Michael; Charola A. Elena; Sterflinger, Katja
Link to Google Scholar
0°C 10°C 20°C 30°C 40°C 50°C
75.9%r.h. 75.6%r.h. 75.4%r.h. 75.2%r.h. 75.2%r.h. 74.8%r.h.





Moisture sorption:
Theoretically 1g NaCl can take up 4.3g of moisture, i.e., water vapor. The moisture sorption during varying relative humidity levels is:


Table 3:Moisture sorption in M% after 56 days according to []The entry doesn't exist yet.
Relative humidity during storge/salt phase NaCl
87% RH 153
81% RH 22
79% RH 7



Hydration behavior[edit]

Under normal environmental conditions only halite will crystallize out of a saturated solution. The hydrated form, dihydrate hydrohalite[4] will only precipitate out at temperatures below 0.15°C.


Microscopy[edit]

Laboratory analysis[edit]

Sodium chloride crystals can be reliably identified on the basis of their morphological features. Individual particles usually form cubic or octahedral shapes and, therefore, clearly display right angles in their crystal construction.

Refractive index:  nD = 1.544
Crystal category:       cubic

Examination by polarized microscopy:

There are few salts belonging to the cubic crystal system which can be found in masonry, i.e., sodium chloride (halite), potassium chloride (sylvite) and calcium fluoride (flourite). Only the two first salts are highly soluble and therefore they are the ones that can cause damage to the masonry. Because of its isotropic internal structure these salts do not display birefringence.

The refractive index can be measured with the immersion method by using a standard oil with a refractive index of nD =1.518. Halite crystals display the same optical density in every direction so that the speed and orientation of linear polarized light waves are not distorted, therefore, when viewed between crossed polars, the crystals are not visible, i.e., they show "extinction".


Differentiation of halite from similar salts:

The three above mentioned isotropic salts can be easily differentiated.


Table 4: Identification features of other chlorides
Salt phase Identification features
Sylvine KCl Refractive index below 1,518.
Fluorite CaF2 Refractive index below 1,518, barely water soluble.


Images of salts and salt damage[edit]

In situ[edit]

  • Halite crust on a brick surface

    Halite crust on a brick surface

  • Halite whisker

    Halite whisker

Under the polarizing microscope[edit]

  • Precipitated from the evaporation of an aqueous solution of the sample on microscope slides
  • Sodium chloride, precipitate from an aqueous solution on microscope slide

    Sodium chloride, precipitate from an aqueous solution on microscope slide

  • Sodium chloride, precipitate from an aqueous solution on microscope slide

    Sodium chloride, precipitate from an aqueous solution on microscope slide

  • Sodium chloride, precipitate from an aqueous solution on microscope slide

    Sodium chloride, precipitate from an aqueous solution on microscope slide

  • Sodium chloride, precipitate from an aqueous solution on microscope slide

    Sodium chloride, precipitate from an aqueous solution on microscope slide

  • Sodium chloride, precipitate from an aqueous solution on microscope slide

    Sodium chloride, precipitate from an aqueous solution on microscope slide

  • Sodium chloride and calcium sulphate in real sample, precipitate from an aqueous solution on microscopic slide

    Sodium chloride and calcium sulphate in real sample, precipitate from an aqueous solution on microscopic slide

  • Sodium chloride and calcium sulphate in real sample, precipitate from an aqueous solution on microscopic slide

    Sodium chloride and calcium sulphate in real sample, precipitate from an aqueous solution on microscopic slide


Scanning Electron Microscope photomicrographs[edit]

  • NaCl whisker growing on brick from a church in Venice. The sample had been kept in a film cartridge so it dried out very slowly. A nice cubic crystal can be seen at the tip of the whisker that had been on the surface of the brick as efflorescence when the sample was taken.

    NaCl whisker growing on brick from a church in Venice. The sample had been kept in a film cartridge so it dried out very slowly. A nice cubic crystal can be seen at the tip of the whisker that had been on the surface of the brick as efflorescence when the sample was taken.

Weblinks[edit]

  1. ↑ http://webmineral.com/data/Halite.shtml accessed 28.07.2010
  2. ↑ http://www.mindat.org/min-1804.html accessed 28.07.2010
  3. ↑ http://www.mineralienatlas.de/lexikon/index.php/MineralData?mineral=Halit accessed 28.07.2010
  4. ↑ 4.0 4.1 http://www.mineralienatlas.de/lexikon/index.php/MineralData?mineral=Hydrohalit accessed 28.07.2010

Literature[edit]

[Dana:1951]Dana E.S. (eds.) Dana J.D. (1951): Dana's System of Mineralogy, 7, Wiley & SonsLink to Google Scholar
[Robie.etal:1978]Robie R.A., Hemingway B.S.; Fisher J.A. (1978): Thermodynamic properties of minerals and related substances at 298.15 K and 1 bar pressure and higher temperatures. In: U.S. Geol. Surv. Bull, 1452 ()Link to Google Scholar
[Steiger]The entry doesn't exist yet.
[Steiger.etal:2008c]Steiger, Michael; Kiekbusch, Jana; Nicolai, Andreas (2008): An improved model incorporating Pitzer’s equations for calculation of thermodynamic properties of pore solutions implemented into an efficient program code. In: Construction and Building Materials, 22 (8), 1841-1850, 10.1016/j.conbuildmat.2007.04.020Link to Google Scholar
[Steiger.etal:2014]Steiger, Michael; Charola A. Elena; Sterflinger, Katja (2014): Weathering and Deterioration. In: Siegesmund S.; Snethlage R. (eds.): Stone in Architecture, Springer Verlag Berlin Heidelberg, 223-316, 10.1007/978-3-642-45155-3_4.Link to Google Scholar
[Vogt.etal:1993]Vogt, R.; Goretzki, Lothar (1993): Der Einfluss hygroskopischer Salze auf die Gleichgewichtsfeuchte und Trocknung anorganischer Baustoffe, unveröffentlichter Bericht.Link to Google Scholar
[Winkler:1975] Winkler, Erhard M. (1975): Stone: Properties, Durability in Man´s Environment, Springer Verlag, WienLink to Google Scholar

More Literature

[Biscontin.etal:1988]Biscontin, G.; Driussi, G.; Masin, A.; Zendri, E. (1988): Study on stones artificially salted with MgSO4*7H2O and NaCl and treated with siliconic resin. In: Ciabach, J. (eds.): Proceedings of the 6th International Congress on Deterioration and Conservation of Stone,Nicholas Copernicus University 194-206.Link to Google Scholar
[Brown.etal:2000]Brown, P. W.; Badger, S. (2000): The distributions of bound sulfates and chlorides in concrete subjected to mixed NaCl, MgSO4, Na2SO4 attack. In: Cem. Concr. Res., 30 (10), 1535-1542Link to Google Scholar
[Brown.etal:2001]Brown, P. W.; Badger, S. (2001): Reply to the discussion by William G. Hime and Stella L. Marusin of the paper "The distribution of bound sulfates and chlorides in concrete to mixed NaCl, MgSO4, Na2SO4 attack". In: Cem. Concr. Res., 31 (7), 1117-1118Link to Google Scholar
[Dorn.etal:2007]Dorn, Joachim; Steiger, Michael (2007): Measurement and Calculation of Solubilities in the Ternary System NaCH3COO + NaCl + H2O from 278 K to 323 K. In: Journal of Chemical and Engineering Data, 5 (52), 1784-1790, 10.1021/je7001495Link to Google Scholar
[Friedel:1978]Friedel, B. (1978): Gipslöslichkeiten in wässerigen Systemen mit NaCl, MgCl2, Na2SO4 und MgSO4. In: Zeitschrift für Pflanzenernährung und Bodenkunde, 141 (3), 337-346, 10.1002/jpln.19781410309Link to Google Scholar
[Glasner.etal:1974]Glasner, A.; Zidon, M. (1974): The crystallization of NaCl in the presence of (Fe(CN)6)4- ions. In: Journal of Crystal Growth, 21 (2), 294-304, 10.1016/0022-0248(74)90018-9Link to Google Scholar
[Linnow.etal:2007c]Linnow, Kirsten; Juling, Herbert; Steiger, Michael (2007): Investigation of NaCl deliquescence in porous substrates using RH-XRD. In: Environmental Geology, 52 (2), 317-327, 10.1007/s00254-006-0590-9Link to Google Scholar
[Lubelli.etal:2006]Lubelli, B.; van Hees, R.P.J.; Huinik, H.P.; Groot, C.J.W.P. (2006): Irreversible dilation of NaCl contaminated lime–cement mortar due to crystallization cycles. In: Cement and Concrete Research, 36 (4), 678-687, 10.1016/j.cemconres.2005.10.008Link to Google Scholar
[Lubelli.etal:2006a]Lubelli, B.; van Hees, R.P.J.; Huinink, H.P. (2006): Effect of NaCl on the hydric and hygric dilation behaviour of lime-cement mortar. In: HERON, 51 (1), 33-48Link to Google ScholarFulltext link
[Marliacy.etal:2000]Marliacy, P.; Solimando, R.; Bouroukba, M.; Schuffenecker, L. (2000): Thermodynamics of crystallization of sodium sulfate decahydrate in H2O-NaCl-Na2SO4: application to Na2SO4.cntdot.10H2O-based latent heat storage materials. In: Thermochim. Acta, 344 (1), 85-94Link to Google Scholar
[Monnin:1990]Monnin, C. (1990): The influence of pressure on the activity coefficients of the solutes and on the solubility of minerals in the system Na-Ca-Cl-SO4-H2O to 200°C and 1 kbar, and to high NaCl concentration. In: Geochimica et Cosmochimica Acta, 54 (12), 3265-3282, 10.1016/0016-7037(90)90284-RLink to Google Scholar
[Moropoulou.etal:1992]Moropoulou, Antonia; Theoulakis, Panagiotis (1992): Conditions causing destructive NaCl crystallization into the porous sandstone, building material of the medieval city of Rhodes. In: Decrouez, Danielle; Chamay, Jacques; Zezza, Fulvio (eds.): The conservation of monuments in the Mediterranean Basin: proceedings of the 2nd international symposium, Musee d'Art et d'Histoire-Geneve; Museum d'Histoire Naturelle, 493-499.Link to Google Scholar
[Ottosen.etal:2017]Ottosen, Lisbeth M.; Andersson, Lovisa C. H. (2017): Electrode placement during electro-desalination of NaCl contaminated sandstone – simulating treatment of carved stones. In: Laue, Steffen (eds.): Proceedings of SWBSS 2017. Fourth International Conference on Salt Weathering of Buildings and Stone Sculptures, University of Applied Sciences Potsdam, Germany, 20-22 September 2017,Verlag der Fachhochschule Potsdam 150-157, 10.5165/hawk-hhg/332.Link to Google Scholar
[Pitzer:1986]Pitzer, K. S. (1986): Thermodynamics of NaCl in steam. In: Geochemica et Cosmochimica Acta, 50 (7), 1445-1454Link to Google Scholar
[Platford:1975]Platford, R. F. (1975): Thermodynamics of the system H2O-NaCl-MgCl2-Na2SO4-MgSO4 at 25 degrees C. In: Mar. Chem., 3 (4), 261-270Link to Google Scholar
[Potter.etal:1978]Potter, R. W. I.; Clynne, M. A. (1978): Solubility of high soluble salts in aqueous media; Part 1, NaCl, KCl, CaCl2, Na2SO4, and K2SO4 solubilities to 100 degrees C. In: Journal of Research of the U. S. Geological Survey, 6 (6), 701-705Link to Google Scholar
[Ptacek.etal:1992]Ptacek, C. J.; Reardon, E. J. (1992): Solubility of siderite (FeCO3) in concentrated NaCl and Na2SO4 solutions at 25 degrees C. In: Kharaka, Yousif K.; Maest, Ann S. (eds.): Proceedings of the 7th international symposium on water-rock interaction, 181-184.Link to Google Scholar
[Rodriguez-Navarro.etal:2002]Rodriguez-Navarro, Carlos; Linares-Fernandez, Lucia; Doehne, Eric; Sebastian, Eduardo (2002): Effects of ferrocyanide ions on NaCl crystallization in porous stone. In: Journal of Crystal Growth, 243 (3), 503-516, UrlLink to Google Scholar
[Sarada.etal:1990]Sarada, S.; Ananthaswamy, J. (1990): Thermodynamic Properties of Electrolyte Solutions: Emf Study of the System NaCl-Na2SO4-H20 at 25, 35 and 45 ÄC. In: Journal Chem. Soc. Faraday Trans., 86 (1), 81-84Link to Google Scholar
[Shichiri.etal:1965]Shichiri, T.; Kato, N. (1965): The growth and dissolution of NaCl whiskers in aqueous solution. In: Acta Metallurg., 13 (), 785-795Link to Google Scholar
[Shichiri.etal:1967]Shichiri, T.; Kinoshita, H.; Kato, N. (1967): Regrowth of NaCl and KCl whiskers in aqueous solution. In: Peiser, H.S. (eds.): Crystal Growth, , 385-388.Link to Google Scholar
[Shichiri.etal:1968]Shichiri, T.; Kato, N. (1968): Regrowth of NaCl whiskers from pure and poisoned solutions. In: Journal of Crystal Growth, 3/4 (), 384-390, UrlLink to Google Scholar
[Simon:1981]Simon, B. (1981): Dissolution rates of NaCl and KCl in auqeous solution. In: Journal of Crystal Growth, 52 (2), 789-794, UrlLink to Google Scholar
[Simon:1983] (1983): Influence of the direction of the solution flow on the morphology of NaClO3 crystals. In: Journal of Crystal Growth, 61 (1), 167-169, UrlLink to Google Scholar
[Sonnleitner:2011]Sonnleitner,Tobias (2011): Symmetrien und Manipulation des Ladungszustands von Molekülen auf NaCl-Filmen, Url.Link to Google Scholar
[Tishchenko.etal:1992]Tishchenko, Pavel Ya.; Bychkov, Alexander S.; Hravéczy-Páll, Andrea; Tóth, Klára; Pungor, Ernoe (1992): Activity Coefficients for the System NaCl + Na2SO4 + H2O at Various Temperatures. Application of Pitzer's Equations. In: Journal of Solution Chemistry, 21 (3), 261-274Link to Google Scholar
[Vazquez.etal:2014]Vázquez, P.; Thomachot-Schneider, C.; Mouhoubi, K.; Gommeaux, M.; Fronteau, G.; Barbin, V.; Bodnar, J.L. (2014): Study of NaCl crystallization using Infrared Thermography. In: Hilde De Clercq (eds.): Proceedings of SWBSS 2014 3rd International Conference on Salt Weathering of Buildings and Stone Sculptures,KIK-IRPA, Royal Institute for Cultural Heritage Brussels 289-303, 10.5165/hawk-hhg/274.Link to Google ScholarFulltext link
[Wolf.etal:1992]Wolf, Manfred; Rohde, Harald (1992): Solubility of calcite in mixed aqueous solutions of NaCl and KCl at 25 degrees C and CO2 partial pressures of about 1 kPa. In: Proceedings of the 7th international symposium on water rock interaction, 7 (), 195Link to Google Scholar
[Yellin.etal:1985]Yellin, N.; Zelingher, N.; Ben-Dor, L. (1985): Whiskers growth by means of cellulose acetate membranes: NaCl and KCl. In: Journal of Crystal Growth, 71 (2), 427-432, UrlLink to Google Scholar
[Zdanovskii.etal:1991]Zdanovskii, A. B.; Frolovskii, E. E. (1991): Equations for calculating the solubility of mirabilite in the aqueoussodium chloride-magnesium sulfate (2NaCl + MgSO4 = Na2SO4 + MgCl2) system at 0-25.degree. In: Zh. Prikl. Khim. (Leningrad), 64 (6), 1153-7Link to Google Scholar
[Zelingher:1975]Zelingher, N. (1975): A new method of growing NaCl and KCl whiskers. In: Acta Crystallogr., A 31 Suppl., (), 211Link to Google Scholar

A phase is a physically distinctive form of matter and is characterized by having relatively uniform chemical and physical properties.

crystallization of a dissolved salt

Water glass is the common name for a liquid solution of alkaline silicates, also known as Sodium silicate Na2SiO3 or liquid glass.

concentration given as amount of substance (mol) of the dissolved substance per kilogram solvent; unit: mol•kg-1.

the relative humidity, above which a material, e.g. a salt, absorbes humidity from the air and dissolves.

relative humidity

the mathematical difference between the largest and smallest refractive index for an anisotropic mineral

X-ray diffraction

Retrieved from "https://www.saltwiki.net/index.php?title=Halite&oldid=6449"