Anhydrite is an anhydrous mineral closely related to gypsum. Anhydrite is most frequently found in evaporite deposits with gypsum; it was, for instance, first discovered, in 1794, in a salt mine near Hall in Tirol. In this occurrence, depth is critical since nearer the surface anhydrite has been altered to gypsum by absorption of circulating ground water. The name anhydrite was given by A. G. Werner in 1804, because of the absence of water of crystallization, as contrasted with the presence of water in gypsum. Some obsolete names for the species are muriacite and karstenite; the former, an earlier name, being given under the impression that the substance was a chloride (muriate). A peculiar variety occurring as contorted concretionary masses is known as tripe-stone, and a scaly granular variety, from Volpino, near Bergamo, in Lombardy, as vulpinite; the latter is cut and polished for ornamental purposes.
Within the metaphysical realm of minerals, anhydrite acts something like a radar detector. It has a way of finding toxins and energy blocks within the body. When the toxin or blockage is identified the anhydrite works energetically to cause release. It balances hormones, which are upset by toxins and stress. It allows the believer to understand their physical body and to do what is necessary to begin healing. Some like to use Anhydrite to recognize that one's past is gone, they can keep the beautiful memories but must move onto the next segment of their lives.
Please note that MIROFOSS does not suggest in any way that minerals should be used in place of proper medical and psychological care. This information is provided here as a reference only.
Anhydrite can be used, in many cases, as a substitude for gypsum in building materials and for calcium enrichment in agriculture. Anhydrite can also be used, in small quantities, as a drying agent in paint and plaster.
Anhydrite is found in sedimentary evaporite deposits and in the cap rock of salt domes.
Anhydrite occurs in a tidal flat environment in the Persian Gulf sabkhas as massive diagenetic replacement nodules. Cross sections of these nodular masses have a netted appearance and have been referred to as chicken wire anhydrite. Nodular anhydrite occurs as replacement of gypsum in a variety of sedimentary depositional environments. Massive amounts of anhydrite occur when salt domes form a caprock. Anhydrite is 1–3% of the salt in salt domes and is generally left as a cap at the top of the salt when the halite is removed by pore waters. The typical cap rock is a salt, topped by a layer of anhydrite, topped by patches of gypsum, topped by a layer of calcite.Interaction with oil can reduce sulfate levels creating calcite, water, and hydrogen sulfide. Anhydrite is not isomorphous with the orthorhombic barium (barite) and strontium (celestine) sulfates, as might be expected from the chemical formulas. Distinctly developed crystals are somewhat rare, the mineral usually presenting the form of cleavage masses.
Other than in the basic mineral form, anhydrite can be found in three distinct varieties:
| Cleavage | Perfect to Good | |
| Colour(s) | Colourless, White, Bluish white, Violet white, Dark gray | |
| Specific Gravity | 2.97 | |
| Diaphaneity | Translucent to Transparent | |
| Fracture | Brittle | |
| Mohs Hardness | 3.5 | |
| Luminescence | Non-fluorescent | |
| Luster | Vitreous | |
| Streak | White | |
| Habit(s) | Fibrous to Granular to Plumose | |
| Radioactivity | Non-radioactive | |
| Magnetism | Non-magnetic |
No known health risks have been associated with anhydrite. However ingestion of anhydrite, as with other naturally occurring minerals, is not recommended.
The following image shows the Elemental breakdown of the mineral anhydrite along with the mineral crystal structure.
| Crystal System | Orthorhombic |  |
| Class | Dipyramidal | |
| Axial Ratios | a : b : c = 0.893 : 1 : 1 | |
| Optical Data Type | Biaxial (+) | |
| Pleochroism (x) | Colourless | |
| Pleochroism (y) | Colourless | |
| RL Values | nα = 1.567 - 1.574 nβ = 1.574 - 1.579 nγ = 1.609 - 1.618 | |
| 2V | Measured: 36° to 45°, Calculated: 44° |  |
| Max Birefringence | δ = 0.042 - 0.044 (See colour chart at right) | |
| Surface Relief | Low | |
| Dispersion | Strong r < v | |
| Notes: |
Anhydrite can be referenced in certain current and historical texts under the following six names:
The mineral anhydrite can be translated into the following select languages:
| Arabic | الأنهيدريت | Bulgarian | Ангидрит | Chinese (Sim) | 硬石膏 |
| Croatian | anhidrit | Czech | Anhydrit | Danish | anhydrit |
| Dutch | Anhydriet | Esperanto | Anhidrito | Estonian | Anhüdriitpinnad |
| Finnish | anhydriitti | French | Anhydrite | German | Anhydrit |
| Greek | ανυδρίτης | Hebrew | אנהידריט | Hungarian | Anhidrit |
| Italian | Anidrite | Japanese | 硬石膏 | Korean | 경석고 |
| Latin | Anhydrite | Lithuanian | Anhidritas | Norwegian | anhydritt |
| Persian | انیدریت | Polish | Anhydryt | Portuguese | Anidrita |
| Romanian | anhidrit | Russian | Ангидрит | Slovak | Anhydrit |
| Spanish | Anhidrita | Swedish | Anhydrit | Tagalog | anhidrit |
| Turkish | anhidrit | Ukrainian | Ангідрит | Vietnamese | thứ thạch cao cứng |
Anhydrite is considered to be very abundant around the world. The map below shows major documented concentrations of Anhydrite:
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The MIROFOSS database offers free printable geological identification tags for personal and non-profit use. These tags can be used to properly identify mineral samples in your collection. -Click here- to download a full size jpeg image for an anhydrite identification tag; which can be printed on paper or used with a plastic laser printer. |
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What's this? What can I do with it? |
| Chemical Composistion | Anthony, J.W., Bideaux, R.A., Bladh, K.W., and Nichols, M.C. (2003) Handbook of Mineralogy, Volume V. Borates, Carbonates, Sulfates. Mineral Data Publishing, Tucson, AZ, 813pp.: 25. |
| Crystallography | Hardie, L.A. (1967), The gypsum-anhydrite equilibrium at one atmosphere pressure: American Mineralogist: 52: 171-200. |
| History | Canadian Mineralogist (1975): 13: 289-292. |
| History | Palache, C., Berman, H., & Frondel, C. (1951), The System of Mineralogy of James Dwight Dana and Edward Salisbury Dana, Yale University 1837-1892, Volume II. John Wiley and Sons, Inc., New York, 7th edition, revised and enlarged: 407, 424-428. |
| Geograpcial Data | Mindat.org. Retrieved on 2013-02-04 |
| Physical Identification | Webmineral.com. Retrieved on 2013-02-04. |
| February 07, 2013 | The last time this page was updated |
| ©2019 MIROFOSS™ Foundation | |
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