登录
Gunmaite
A valid IMA mineral species
This page is currently not sponsored. Click here to sponsor this page.
About Gunmaite
Formula:
(Na2Sr)Sr2Al10(PO4)4F14(OH)12
Colour:
colorless
Lustre:
Resinous, Greasy
Hardness:
5
Specific Gravity:
3.38 (Calculated)
Crystal System:
Trigonal
Name:
For the type locality.
Unique combination of elements (status: Nov. 2022).
Structurally related to alunite supergroup.
Both gunmaite and the co-described kiryuite are products of the final stage of hydrothermal activity during greisenization.
Structurally related to alunite supergroup.
Both gunmaite and the co-described kiryuite are products of the final stage of hydrothermal activity during greisenization.
Unique Identifiers
Mindat ID:
470430
Long-form identifier:
mindat:1:1:470430:6
IMA Classification of Gunmaite
Approved
Approval year:
2022
Type description reference:
Classification of Gunmaite
8.BM.
8 : PHOSPHATES, ARSENATES, VANADATES
B : Phosphates, etc., with additional anions, without H2O
M : With medium-sized and large cations, (OH, etc.):RO4 = 4:1
8 : PHOSPHATES, ARSENATES, VANADATES
B : Phosphates, etc., with additional anions, without H2O
M : With medium-sized and large cations, (OH, etc.):RO4 = 4:1
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 |
|---|---|---|
| Gum | 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 Gunmaite
Resinous, Greasy
Transparency:
Transparent
Colour:
Colorless
Hardness:
5 on Mohs scale
Tenacity:
Brittle
Cleavage:
Perfect
{001}
{001}
Density:
3.38 g/cm3 (Calculated)
Chemistry of Gunmaite
Mindat Formula:
(Na2Sr)Sr2Al10(PO4)4F14(OH)12
Element Weights:
Chemical Analysis
Empirical formulas:
| Sample ID | Empirical Formula |
|---|---|
| 1 | (Na1.72Sr0.70Mg0.56Ca0.01)Σ2.99(Sr1.32Ba0.68)Σ2(Al9.82Mg0.18)Σ10P3.99O16F16.21(OH)9.79 |
Sample references:
| ID | Locality | Reference | Notes |
|---|---|---|---|
| 1 | Vein No. 2, Tsukubara mine, Kiryu City, Gunma Prefecture, Japan | empirical formula basis: O = 16 & F + OH = 26 |
Crystallography of Gunmaite
Crystal System:
Trigonal
Class (H-M):
3m(32/m) - Hexagonal Scalenohedral
Space Group:
R3m
Setting:
R3m
Cell Parameters:
a = 6.9972(2) Å, c = 50.270(2) Å
Ratio:
a:c = 1 : 7.184
Unit Cell V:
2,131.51 ų (Calculated from Unit Cell)
Z:
3
Comment:
crystals contained stacking faults
X-Ray Powder Diffraction
Powder Diffraction Data:
| d-spacing | Intensity |
|---|---|
| 5.458 Å | (80) |
| 3.499 Å | (57) |
| 3.228 Å | (29) |
| 2.965 Å | (100) |
| 2.233 Å | (35) |
| 2.138 Å | (49) |
| 1.900 Å | (59) |
| 1.749 Å | (64) |
Reference:
Type Occurrence of Gunmaite
General Appearance of Type Material:
occurs as the core in hexagonal tablet crystals, and gorceixite and goyazite like mineral with a zonal texture due to the Sr-Ba content are often present at the rim. The outermost rim in the yellow crystal consists of kintoreite or segnitite. The relationship between the core and rim is occasionally reversed, with gunmaite located at the rim. The diameter of the hexagonal crystals can be up to 500 μm, with a thickness of less than 100 μm in many cases. The gunmaite areas are euhedral to subhedral, and up to 200 micrometers in diameter.
Place of Conservation of Type Material:
Type material is deposited in the collections of the National Museum of Nature and Science, Amakubo, Tsukuba, Ibaraki 305-0005, Japan, specimen number NSM-M49762
Geological Setting of Type Material:
products of the final stage of hydrothermal activity in association with greisenization.
Associated Minerals at Type Locality:
Reference:
Synonyms of Gunmaite
Other Language Names for Gunmaite
Common Associates
Related Minerals - Strunz-mindat Grouping
| 8.BM. | Betpakdalite-NaNa | [Na2(H2O)16Na(H2O)6][Mo8As2Fe3+3O33(OH)4] |
| 8.BM.05 | Retzian-(Ce) | Mn2+2Ce(AsO4)(OH)4 |
| 8.BM.05 | Retzian-(La) | Mn2+2La(AsO4)(OH)4 |
| 8.BM.05 | Retzian-(Nd) | Mn2+2Nd(AsO4)(OH)4 |
| 8.BM.10 | Paulkellerite | (BiO)2Fe3+(PO4)(OH)2 |
| 8.BM.10 | Kolitschite | PbZn0.5Fe3(AsO4)2(OH)6 |
| 8.BM.15 | Brendelite | (Bi3+,Pb)2(Fe3+,Fe2+)(PO4)O2(OH) |
Fluorescence of Gunmaite
none
Other Information
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 Gunmaite
mindat.org URL:
https://www.mindat.org/min-470430.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 Gunmaite
Reference List:
mdcl.issp.u-tokyo.ac.jp (2020) https://mdcl.issp.u-tokyo.ac.jp/denken/?page_id=20#a26
Localities for Gunmaite
Showing 1 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.
Japan (TL) | |
| Nishio-Hamane et al. (2023) |
Quick NavTopAbout GunmaiteUnique IdentifiersIMA Classification Classification Mineral SymbolsPhysical Properties Chemistry Chemical AnalysisCrystallography X-Ray Powder DiffractionType Occurrence SynonymsOther LanguagesCommon AssociatesStrunz-MindatFluorescence Other InformationInternet Links References Localities Locality List
Vein No. 2, Tsukubara mine, Kiryu City, Gunma Prefecture, Japan