Blödite
A valid IMA mineral species - grandfathered
This page is currently not sponsored. Click here to sponsor this page.
About Blödite
Formula:
Na2Mg(SO4)2 · 4H2O
May contain some K replacing Na.
Colour:
Colourless, bluish-green, reddish; colourless in transmitted light.
Lustre:
Vitreous
Hardness:
2½ - 3
Specific Gravity:
2.218 - 2.24
Crystal System:
Monoclinic
Member of:
Name:
Named in honor of Carl (Karl) August Blöde (14 August 1773, Freiberg Saxony, Germany - 28 August 1820) German Privy Financial Councilor, chemist and author. The variant spelling bloedite was rejected by the IMA in 1960.
Name Encoding
ASCII-7:
Blodite
Unique Identifiers
Mindat ID:
695
Long-form identifier:
mindat:1:1:695:8
Similar Names
| Baldite | A rock subtype |
IMA Classification of Blödite
Approved, 'Grandfathered' (first described prior to 1959)
IMA Formula:
Na2Mg(S6+O4)2·4H2O
First published:
1821
Classification of Blödite
7.CC.50
7 : SULFATES (selenates, tellurates, chromates, molybdates, wolframates)
C : Sulfates (selenates, etc.) without additional anions, with H2O
C : With medium-sized and large cations
7 : SULFATES (selenates, tellurates, chromates, molybdates, wolframates)
C : Sulfates (selenates, etc.) without additional anions, with H2O
C : With medium-sized and large cations
29.3.3.1
29 : HYDRATED ACID AND NORMAL SULFATES
3 : A2B(XO4)2·xH2O
29 : HYDRATED ACID AND NORMAL SULFATES
3 : A2B(XO4)2·xH2O
25.3.9
25 : Sulphates
3 : Sulphates of Mg
25 : Sulphates
3 : Sulphates of Mg
Mineral Symbols
As of 2021 there are now IMA–CNMNC approved mineral symbols (abbreviations) for each mineral species, useful for tables and diagrams.
| Symbol | Source | Reference for Standard |
|---|---|---|
| Blö | IMA–CNMNC | Warr, L.N. (2021). IMA–CNMNC approved mineral symbols. Mineralogical Magazine, 85(3), 291-320. doi:10.1180/mgm.2021.43 |
Physical Properties of Blödite
Vitreous
Transparency:
Transparent
Colour:
Colourless, bluish-green, reddish; colourless in transmitted light.
Hardness:
2½ - 3 on Mohs scale
Tenacity:
Brittle
Cleavage:
None Observed
Fracture:
Conchoidal
Density:
2.218 - 2.24 g/cm3 (Measured) 2.23 g/cm3 (Calculated)
Optical Data of Blödite
Type:
Biaxial (-)
RI values:
nα = 1.483 nβ = 1.486 nγ = 1.487
2V:
Measured: 71° , Calculated: 58°
Max. Birefringence:
δ = 0.004
Based on recorded range of RI values above.
Based on recorded range of RI values above.
Interference Colours:
The colours simulate birefringence patterns seen in thin section under crossed polars. They do not take into account mineral colouration or opacity.
Michel-Levy Bar The default colours simulate the birefringence range for a 30 µm thin-section thickness. Adjust the slider to simulate a different thickness.
Grain Simulation You can rotate the grain simulation to show how this range might look as you rotated a sample under crossed polars. Each grain retains its interference colour (retardation) while its brightness falls to black at extinction and reaches a maximum between extinction positions.
The colours simulate birefringence patterns seen in thin section under crossed polars. They do not take into account mineral colouration or opacity.
Michel-Levy Bar The default colours simulate the birefringence range for a 30 µm thin-section thickness. Adjust the slider to simulate a different thickness.
Grain Simulation You can rotate the grain simulation to show how this range might look as you rotated a sample under crossed polars. Each grain retains its interference colour (retardation) while its brightness falls to black at extinction and reaches a maximum between extinction positions.
Surface Relief:
Moderate (negative)
Relative to Canada balsam mounting medium (n ≈ 1.537).
Relative to Canada balsam mounting medium (n ≈ 1.537).
This shows the grain boundary and Becke line effect under plane-polarised
light, based on the contrast between this mineral's average refractive
index and the mounting medium. It does not take into account mineral
colouration.
In focus
Interference Figure:
This shows the idealized biaxial acute bisectrix (Bxa) interference figure
- the conoscopic view for a grain cut perpendicular to the acute bisectrix, using
this mineral's 2V. The two small white dots mark the melatopes - the points
where the two optic axes emerge - and are shown only when they fall within the
field of view. The coloured bands are isochromatics, and the dark bands are
isogyres.
Rotate the stage: at 0°/90° the isogyres form a cross through the melatopes; at 45° they pull apart into curved hyperbolas. That splitting on rotation - absent in a uniaxial figure - is the standard diagnostic test for telling biaxial minerals from uniaxial ones. If 2V is large, the melatopes may fall outside the field of view, as they often do at the microscope too.
Rotate the stage: at 0°/90° the isogyres form a cross through the melatopes; at 45° they pull apart into curved hyperbolas. That splitting on rotation - absent in a uniaxial figure - is the standard diagnostic test for telling biaxial minerals from uniaxial ones. If 2V is large, the melatopes may fall outside the field of view, as they often do at the microscope too.
Dispersion:
relatively strong
Chemistry of Blödite
Mindat Formula:
Na2Mg(SO4)2 · 4H2O
May contain some K replacing Na.
May contain some K replacing Na.
Element Weights:
Crystallography of Blödite
Crystal System:
Monoclinic
Class (H-M):
2/m - Prismatic
Space Group:
P21/b
Setting:
P21/a
Cell Parameters:
a = 11.04 Å, b = 8.15 Å, c = 5.49 Å
β = 100.41°
β = 100.41°
Ratio:
a:b:c = 1.355 : 1 : 0.674
Unit Cell V:
485.84 ų (Calculated from Unit Cell)
Z:
2
Morphology:
Crystals short prismatic [001], frequently highly modified. Massive, granular or compact.
Crystallographic forms of Blödite
Crystal Atlas:
Image Loading
Click on an icon to view
Blödite no.1 - {110} - Goldschmidt (1913-1926)
Blödite no.4 - {111} - Goldschmidt (1913-1926)
3d models and HTML5 code kindly provided by
www.smorf.nl.
Toggle
Edge Lines | Miller Indices | Axes
Transparency
Opaque | Translucent | Transparent
View
Along a-axis | Along b-axis | Along c-axis | Start rotation | Stop rotation
Edge Lines | Miller Indices | Axes
Transparency
Opaque | Translucent | Transparent
View
Along a-axis | Along b-axis | Along c-axis | Start rotation | Stop rotation
X-Ray Powder Diffraction
Loading XRD data...
Data courtesy of RRUFF project at University of Arizona, used with permission.
Powder Diffraction Data:
| d-spacing | Intensity |
|---|---|
| 3.252 Å | (100) |
| 4.555 Å | (95) |
| 3.289 Å | (95) |
| 2.971 Å | (40) |
| 2.732 Å | (40) |
| 4.281 Å | (30) |
| 2.025 Å | (30) |
Geological Environment
Paragenetic Mode(s):
| Paragenetic Mode | Earliest Age (Ga) |
|---|---|
| Near-surface Processes | |
| 25 : Evaporites (prebiotic) | |
| Stage 7: Great Oxidation Event | <2.4 |
| 45a : [Sulfates, arsenates, selenates, antimonates] | |
| 47a : [Near-surface hydration of prior minerals] | |
| 47b : [Sulfates and sulfites] | |
| Stage 10a: Neoproterozoic oxygenation/terrestrial biosphere | <0.6 |
| 50 : Coal and/or oil shale minerals | <0.36 |
| Stage 10b: Anthropogenic minerals | <10 Ka |
| 54 : Coal and other mine fire minerals (see also #51 and #56) |
Geological Setting:
Oceanic salt deposits; lacustrine salt deposits; nitrate deposits in arid regions.
Type Occurrence of Blödite
Place of Conservation of Type Material:
No designated type material.
Geological Setting of Type Material:
Oceanic salt deposit.
Associated Minerals at Type Locality:
Synonyms of Blödite
Other Language Names for Blödite
Dutch:Blödiet
Italian:Bloedite
Russian:Бледит
Simplified Chinese:白钠镁矾
Spanish:Astrachanita
Astrakhanita
Blödita
Astrakhanita
Blödita
Traditional Chinese:白鈉鎂礬
Varieties of Blödite
| Natronkalisimonyit | A variety containing a small amount of K (0.43%) |
Relationship of Blödite to other Species
Member of:
Other Members of Blödite Group:
| Changoite | Na2Zn(SO4)2 · 4H2O | Mon. 2/m : P21/b |
| Cobaltoblödite | Na2Co(SO4)2 · 4H2O | Mon. 2/m : P21/b |
| Manganoblödite | Na2Mn(SO4)2 · 4H2O | Mon. 2/m : P21/b |
| Nickelblödite | Na2Ni(SO4)2 · 4H2O | Mon. 2/m : P21/b |
Common Associates
Associations Based on Photo Data:
| 6 photos of Blödite associated with Betpakdalite-NaCa | [Na2(H2O)17Ca(H2O)6][Mo6+8As5+2Fe3+3O34(OH)3] |
| 6 photos of Blödite associated with Hexahydrite | Mg(H2O)6(SO4) |
| 6 photos of Blödite associated with Nitratine | NaNO3 |
| 6 photos of Blödite associated with Bandylite | Cu[B(OH)4]Cl |
| 2 photos of Blödite associated with Konyaite | Na2Mg(SO4)2 · 5H2O |
| 2 photos of Blödite associated with Kröhnkite | Na2Cu(SO4)2 · 2H2O |
| 2 photos of Blödite associated with Thénardite | Na2SO4 |
| 1 photo of Blödite associated with Magnesioaubertite | (Mg,Cu)Al(SO4)2Cl · 14H2O |
| 1 photo of Blödite associated with Sideronatrite | Na2Fe(SO4)2(OH) · 3H2O |
| 1 photo of Blödite associated with Meisserite | Na5(UO2)(SO4)3(SO3OH)(H2O) |
Related Minerals - Strunz-mindat Grouping
| 7.CC. | Cobaltoblödite | Na2Co(SO4)2 · 4H2O |
| 7.CC. | Andychristyite | PbCu2+Te6+O5(H2O) |
| 7.CC. | Ammoniovoltaite | (NH4)2Fe2+5Fe3+3Al(SO4)12(H2O)18 |
| 7.CC.05 | Krausite | KFe(SO4)2 · H2O |
| 7.CC.10 | Tamarugite | NaAl(SO4)2 · 6H2O |
| 7.CC.15 | Mendozite | NaAl(SO4)2 · 11H2O |
| 7.CC.15 | Kalinite | KAl(SO4)2 · 11H2O |
| 7.CC.20 | Alum-(Na) | NaAl(SO4)2 · 12H2O |
| 7.CC.20 | Lonecreekite | (NH4)Fe3+(SO4)2 · 12H2O |
| 7.CC.20 | Alum-(K) | KAl(SO4)2 · 12H2O |
| 7.CC.20 | Tschermigite | (NH4)Al(SO4)2 · 12H2O |
| 7.CC.20 | Lanmuchangite | Tl+Al(SO4)2 · 12H2O |
| 7.CC.25 | Zincovoltaite | K2Zn5Fe3+3Al(SO4)12 · 18H2O |
| 7.CC.25 | Voltaite | K2Fe2+5Fe3+3Al(SO4)12 · 18H2O |
| 7.CC.25 | Magnesiovoltaite | K2Mg5Fe3+3Al(SO4)12 · 18H2O |
| 7.CC.25 | Pertlikite | K2(Fe2+,Mg)2(Mg,Fe3+)4Fe3+2Al(SO4)12 · 18H2O |
| 7.CC.25 | Ammoniomagnesiovoltaite | (NH4)2Mg2+5Fe3+3Al(SO4)12 · 18H2O |
| 7.CC.30 | Kröhnkite | Na2Cu(SO4)2 · 2H2O |
| 7.CC.35 | Ferrinatrite | Na3Fe(SO4)3 · 3H2O |
| 7.CC.40 | Goldichite | KFe(SO4)2 · 4H2O |
| 7.CC.45 | Löweite | Na12Mg7(SO4)13 · 15H2O |
| 7.CC.50 | Nickelblödite | Na2Ni(SO4)2 · 4H2O |
| 7.CC.50 | Changoite | Na2Zn(SO4)2 · 4H2O |
| 7.CC.55 | Leonite | K2Mg(SO4)2 · 4H2O |
| 7.CC.55 | Mereiterite | K2Fe(SO4)2 · 4H2O |
| 7.CC.60 | Nickelpicromerite | K2Ni(SO4)2 · 6H2O |
| 7.CC.60 | Nickelboussingaultite | (NH4)2Ni(SO4)2 · 6H2O |
| 7.CC.60 | Katerinopoulosite | (NH4)2Zn(SO4)2 · 6H2O |
| 7.CC.60 | Picromerite | K2Mg(SO4)2 · 6H2O |
| 7.CC.60 | Cyanochroite | K2Cu(SO4)2 · 6H2O |
| 7.CC.60 | Mohrite | (NH4)2Fe(SO4)2 · 6H2O |
| 7.CC.60 | Boussingaultite | (NH4)2Mg(SO4)2 · 6H2O |
| 7.CC.65 | Polyhalite | K2Ca2Mg(SO4)4 · 2H2O |
| 7.CC.70 | Leightonite | K2Ca2Cu(SO4)4 · 2H2O |
| 7.CC.75 | Amarillite | NaFe(SO4)2 · 6H2O |
| 7.CC.80 | Konyaite | Na2Mg(SO4)2 · 5H2O |
| 7.CC.85 | Wattevilleite | Na2Ca(SO4)2 · 4H2O (?) |
| 7.CC.85 | Xocolatlite | Ca2Mn4+2(Te6+O6)2 · H2O |
| 7.CC.90 | Eckhardite | (Ca,Pb)Cu2+Te6+O5(H2O) |
Other Information
Thermal Behaviour:
dehydration, endothermic, occurs at 380 and 500 K; first product is löweite; at the second step this transforms into α-Na2Mg2(SO4)3 and vanthoffite or thénardite; the α-Na2Mg2(SO4)
Notes:
Readily soluble in cold water.
Health Risks:
No information on health risks for this material has been entered into the database. You should always treat mineral specimens with care.
Internet Links for Blödite
mindat.org URL:
https://www.mindat.org/min-695.html
Please feel free to link to this page.
Please feel free to link to this page.
Search Engines:
External Links:
Mineral Dealers:
References for Blödite
Reference List:
Froehlich, W. (1929) Neuere Forschungsergebnisse über das System MgSO4-Na2SO4-H2O. Zeitschrift für Angewandte Chemie, 42 (24). p.660-662. doi:10.1002/ange.19290422403
Schaller, Waldemar T. (1932) The refractive indices of bloedite. American Mineralogist, 17 (11) 530-533
(1962) International Mineralogical Association: Commission on New Minerals and Mineral Names. Mineralogical Magazine and Journal of the Mineralogical Society, 33 (258) 260-263 doi:10.1180/minmag.1962.033.258.09
Hey, M. H. (1982) International Mineralogical Association: Commission on New Minerals and Mineral Names. Mineralogical Magazine, 46 (341) 513-514 doi:10.1180/minmag.1982.046.341.25
Lane, M. D. (2007) Mid-infrared emission spectroscopy of sulfate and sulfate-bearing minerals. American Mineralogist, 92 (1) 1-18 doi:10.2138/am.2007.2170
Localities for Blödite
Showing 178 localities.
symbol to view information about a locality.
The Locality List
- This locality has map coordinates listed.
- This locality has estimated coordinates.
ⓘ - Click for references and further information on this occurrence.
? - Indicates mineral may be doubtful at this locality.
- Good crystals or important locality for species.
- World class for species or very significant.
(TL) - Type Locality for a valid mineral species.
(FRL) - First Recorded Locality for everything else (eg varieties).
All localities listed without proper references should be considered as questionable.
Antarctica | |
| Hodenberg et al. (1983) +1 other reference |
| Hodenberg et al. (1983) +1 other reference |
| Vennum (1986) |
Argentina | |
| Benedetto et al. (1998) |
Asia | |
| Crétaux et al. (2009) | |
Australia | |
| Costas Constantinides collection (Ian Graham) |
| Wilson et al. (2014) |
| Mills et al. (2010) | |
Austria | |
| Strasser (1989) |
| Strasser (1989) | |
| Strasser (1989) | |
| Strasser (1989) |
| Strasser (1989) |
| Palache et al. (1951) +2 other references |
| Palache et al. (1951) +1 other reference |
| Palache et al. (1951) +2 other references |
Canada | |
| Kohut et al. (1993) | |
| Renaut et al. (1994) |
| Peatfield (n.d.) |
| Peatfield (n.d.) +1 other reference | |
| Peatfield (n.d.) | |
| Peatfield (n.d.) | |
| Peatfield (n.d.) | |
| Woodside collection |
| Can Min vol 25 pp 221-226 (1987) |
| Zodrow (1989) |
| Last (1990) |
| Shang (2000) | |
| Greengrass et al. (1999) | |
Cape Verde | |
| Silva et al. (2019) |
Chile | |
| e-rocks.com (2022) |
| www.mindat.org (n.d.) +1 other reference |
| samples analysed by Gerhard Mohn and ... |
| Palache et al. (1908) +3 other references |
| De Waele et al. (2017) |
| Aguilera et al. (2016) | |
| Collao et al. (2002) |
| Marta et al. (1996) +1 other reference |
| Pueyo et al. (2021) |
| Wet Chemical by Gerhard Möhn |
| Ericksen et al. (1989) |
China | |
| Zhenmin Liu et al. (2007) |
| Sun Da-peng et al. (2002) |
| Shaoxiu (1991) +1 other reference |
| Mianping Zheng (1997) | |
| Xiyu Zheng (1994) |
| Mianping Zheng (1997) | |
| Shaoxiu (1991) | |
| Mianping Zheng (1997) |
| Qinghai Institute of Salt Lakes website | |
| Shaoxiu (1991) | |
| Shaoxiu (1991) | |
| Zhongde Zhu (1988) |
| Zheng Mianping et al. (1993) |
| Xifang Liu and Mianping Zheng (2010) |
| Okada et al. (1994) |
| Tang (2005) |
| Bingxiao (1992) | |
| Tang (2005) | |
| Bingxiao (1992) |
| Tang (2005) |
| Tang (2005) |
| Zhaoxin Han et al. (2004) +1 other reference |
Costa Rica | |
| Ulloa et al. (2018) |
Czech Republic | |
| Matýsek et al. (2014) |
| Matýsek et al. (2026) | |
El Salvador | |
| Stoiber et al. (1974) |
France | |
| Naze-Nancy Masalehdani et al. (2009) |
| D. Laurent et al. (2023) |
| Steven M. Richardson (1978) |
Germany | |
| Weiß (1990) |
| Krah et al. (1988) | |
| Weiß (1990) |
| Weiß (1990) |
| Weiß (1990) |
| Naumann |
| Brockt et al. (2001) |
| Thalheim +1 other reference |
| W.I. Borrisenkow (1968) |
Hungary | |
| Mecsek-Oko |
Iceland | |
| Jakobsson et al. (1992) |
India | |
| Sinha et al. (2003) |
Italy | |
| Russo et al. (2017) |
| Russo et al. (2022) | |
| Mezzadri (1988) |
| Palache et al. (1951) |
| www.cse.speleo.it |
| Garavelli et al. (1996) |
Kazakhstan | |
| Pekov et al. (1993) |
| Rose (1842) +2 other references |
Kenya | |
| Bowell et al. (1996) |
Mexico | |
| Gazquez et al. (1) |
Namibia | |
| Dill et al. (2002) |
New Zealand | |
| Kerr et al. (2017) |
Pakistan | |
| Specimen in collection of Natural ... |
| Dana 6: 899 +1 other reference | |
| Specimen in collection of Natural ... |
| Dana 6: 947 +1 other reference |
Peru | |
| Tyc et al. (2022) |
| Tyc et al. (2022) | |
| Tyc et al. (2022) | |
| Diaby et al. (2006) |
Poland | |
| Lukasz Kruszewski 2005: Minerals arising in cause of underground fires of "Skalny" coal mine dump in Laziska (Upper Silesia, Poland) |
| Kruszewski (2013) |
| Kruszewski (2013) | |
| Ł. Kruszewski PXRD data (to be published soon) |
Portugal | |
| Joana Ribeiro et al. (2013) |
Russia | |
| Rose (1842) +3 other references | |
| Ryabin et al. (1920) +1 other reference |
| Cesnokov et al. (1998) |
| Mazurov et al. (2007) |
| Ryabin et al. (1920) +1 other reference |
| Pekov et al. (2012) |
| Gerhard Möhn collection | |
| Pekov et al. (2019) | |
| Okrugin (2004) |
| Sadykov et al. (2020) |
| Naumov et al. (2008) |
| Kasatkin et al. (2014) |
Slovakia | |
| Szakáll et al. (2014) |
Spain | |
| Georges FAVREAU collection & EDX ... |
| Vizcayno et al. (1995) |
| Vizcayno et al. (1995) |
| Vizcayno et al. (1995) | |
| Mees et al. (2011) |
| Campeny et al. (2023) |
| Calvo Rebollar (2014) |
Tajikistan | |
| Badalov et al. (1975) |
| Badalov et al. (1975) | |
Tanzania | |
| Mason (1962) |
Turkey | |
| Helvaci (1998) |
| Karakaya et al. (1984) |
| van Doesburg et al. (1982) |
| Vergouwen (1981) |
| Altay et al. (2010) |
Turkmenistan | |
| Evseev (1995) +1 other reference |
| Palache et al. (1951) | |
Ukraine | |
| Nesterovskiy et al. (2015) | |
| Deyak M.A. Modern water-chemogenic ... |
| Dvoichenko P.A. The minerals of Crimea (1914) |
| Palache et al. (1951) |
USA | |
| Anthony et al. (1995) |
| Murata (1977) +2 other references |
| Murata (1977) +2 other references |
| Murata (1977) +2 other references |
| Sampson (1942) +4 other references |
| Adams et al. (2014) |
| Adams et al. (2014) |
| Adams et al. (2014) | |
| Adams et al. (2014) | |
| Jones (1961) +2 other references |
| Crowley (1996) +1 other reference | |
| Murata (1977) +2 other references |
| Murata (1977) +2 other references |
| Murata (1977) +2 other references |
| Färber (n.d.) |
| Encyclopia of Minerals (Roberts, Rapp, Weber) +1 other reference |
| Gale (1914e) +4 other references |
| Murata (1977) +2 other references |
| Eckel et al. (1997) |
| Eckel et al. (1997) |
| Eckel et al. (1997) |
| Eckel et al. (1997) |
| Zielinski et al. (2001) |
| Hon et al. (2009) |
| Buck et al. (2006) |
| Northrop et al. (1996) |
| Hawley +5 other references |
| 2008 New Mexico Mineral Symposium ... |
| Tankersley et al. (2016) |
| Northrop et al. (1996) |
| USGS Prof Paper 68 The Ore Deposits of ... +1 other reference | |
| Bullock (1981) |
| Bullock (1981) | |
| Plášil et al. (2013) +1 other reference |
| Bullock (1981) |
| Cannon (1975) |
Uzbekistan | |
| Slyusareva (1969) +1 other reference |
Quick NavTopAbout BlöditeName EncodingUnique IdentifiersSimilar NamesIMA Classification Classification Mineral SymbolsPhysical Properties Optical Data Chemistry Crystallography Crystallographic forms X-Ray Powder DiffractionGeological EnvironmentType Occurrence SynonymsOther LanguagesVarietiesRelationshipsCommon AssociatesStrunz-MindatOther InformationInternet Links References Localities Locality List
Salt mine, Hallstatt, Gmunden District, Upper Austria, Austria