Jahnsite-(NaMnMg) (original) (raw)

A valid IMA mineral species

About Jahnsite-(NaMnMg)Hide

This section is currently hidden. Click the show button to view.

Formula:

{(Na,Ca)}{(Mn2+,Fe3+)}{(Mg,Fe3+)2}{Fe3+2}(PO4)4(OH)2 · 8H2O

Colour:

Light orange to orange-yellow

Crystal System:

Monoclinic

Name:

The root name is in honor of Richard Henry Jahns (March 10, 1915 Los Angeles, California, USA - December 31, 1983 Palo Alto, California, USA), mineralogist and pegmatite expert, Stanford University, Palo Alto, California, USA. The suffix indicates metal site occupancies.

Co-Type Localities:

ⓘ White Rock No. 2 pegmatite, White Rock Feldspar Mine, Old Boolcoomata Station, Bimbowrie Conservation Park, Pastoral Unincorporated Area, South Australia, Australia
ⓘ Sapucaia mine, Sapucaia do Norte, Galiléia, Minas Gerais, Brazil

Unique IdentifiersHide

This section is currently hidden. Click the show button to view.

Long-form identifier:

mindat:1:1:35967:4

7e817e3f-e9ff-45be-806f-60cb810c675f

IMA Classification of Jahnsite-(NaMnMg)Hide

This section is currently hidden. Click the show button to view.

IMA Formula:

(Na,Ca)(Mn2+,Fe3+)(Mg,Fe3+)2Fe3+2(PO4)4(OH)2(H2O)8

Approval history:

Pre-2018: Unnamed, but probably valid.
2018: Approved by IMA as a new species (IMA 2018-017).

Type description reference:

Kampf, A. R., Elliott, P., Nash, B. P., Chiappino, L., & Varvello, S. (2018). Jahnsite-(NaMnMg), a new jahnsite-group mineral from the Sapucaia mine, Brazil and the White Rock No. 2 quarry, Australia. The Canadian Mineralogist, 56(6), 871-882.

Classification of Jahnsite-(NaMnMg)Hide

This section is currently hidden. Click the show button to view.

8.DH.15

8 : PHOSPHATES, ARSENATES, VANADATES
D : Phosphates, etc. with additional anions, with H2O
H : With large and medium-sized cations, (OH, etc.):RO4 < 1:1

42.11.2.8

42 : HYDRATED PHOSPHATES, ETC.CONTAINING HYDROXYL OR HALOGEN
11 : (AB)3(XO4)2Zq·xH2O

Mineral SymbolsHide

This section is currently hidden. Click the show button to view.

As of 2021 there are now IMA–CNMNC approved mineral symbols (abbreviations) for each mineral species, useful for tables and diagrams.

Please only use the official IMA–CNMNC symbol. Older variants are listed for historical use only.

Physical Properties of Jahnsite-(NaMnMg)Hide

This section is currently hidden. Click the show button to view.

Colour:

Light orange to orange-yellow

Fracture:

Irregular/Uneven, Splintery

Density:

2.68(1) g/cm3 (Measured) 2.684 g/cm3 (Calculated)

Optical Data of Jahnsite-(NaMnMg)Hide

This section is currently hidden. Click the show button to view.

RI values:

_n_α = 1.642(1) _n_β = 1.675(1) _n_γ = 1.677(1)

2V:

Measured: 27° (2), Calculated: 27.2°

δ = 0.035

Image shows birefringence interference colour range (at 30µm thickness)
and does not take into account mineral colouration.

Dispersion:

Very strong; r< v

Comments:

X = colorless, Y and Z = orange-yellow

Comments:

Y ≈ Z = X
Optical orientation: Z = b; XΛc = 51° in obtuse b

Chemistry of Jahnsite-(NaMnMg)Hide

This section is currently hidden. Click the show button to view.

Mindat Formula:

{(Na,Ca)}{(Mn2+,Fe3+)}{(Mg,Fe3+)2}{Fe3+2}(PO4)4(OH)2 · 8H2O

Crystallography of Jahnsite-(NaMnMg)Hide

This section is currently hidden. Click the show button to view.

Crystal System:

Monoclinic

Class (H-M):

2/m - Prismatic

Cell Parameters:

a = 15.104(1) Å, b = 7.1629(2) Å, c = 9.8949(7) Å
β = 110.640(7)°

Ratio:

a:b:c = 2.109 : 1 : 1.381

Unit Cell V:

1,001.80 ų (Calculated from Unit Cell)

Morphology:

Elongate on [100], exhibiting the forms {100}, {001}, and {011}.

Twinning:

Ubiquitously twinned by reflection on {001}.

X-Ray Powder DiffractionHide

This section is currently hidden. Click the show button to view.

Powder Diffraction Data:

Geological EnvironmentHide

This section is currently hidden. Click the show button to view.

Type Occurrence of Jahnsite-(NaMnMg)Hide

This section is currently hidden. Click the show button to view.

Co-Type Localities:

ⓘ White Rock No. 2 pegmatite, White Rock Feldspar Mine, Old Boolcoomata Station, Bimbowrie Conservation Park, Pastoral Unincorporated Area, South Australia, Australia
ⓘ Sapucaia mine, Sapucaia do Norte, Galiléia, Minas Gerais, Brazil

General Appearance of Type Material:

Zoned yellow crystals with orange-red bands near their terminations. prisms, elongate on [100].

Place of Conservation of Type Material:

The holotype specimen from the Sapucaia mine is housed in the collections of the Mineral Sciences Department, Natural History Museum of Los Angeles County, 900 Exposition Boulevard, Los Angeles, California 90007, USA, catalogue number 66701. The cotype specimen from the White Rock No. 2 quarry is deposited in the collections of the South Australian Museum, North Terrace, Adelaide, South Australia, Australia, registration number G34298.

Geological Setting of Type Material:

Associated Minerals at Type Locality:

Reference:

Kampf, A.R., Elliott, P., Nash, B.P., Chiappino, L., Varvello, S. (2018) Jahnsite-(NaMnMg), a new jahnsite-group mineral from the Sapucaia mine, Brazil and the White Rock No. 2 quarry, Australia. The Canadian Mineralogist: 56(6): 871-882.

Synonyms of Jahnsite-(NaMnMg)Hide

This section is currently hidden. Click the show button to view.

Relationship of Jahnsite-(NaMnMg) to other SpeciesHide

This section is currently hidden. Click the show button to view.

Other Members of this group:

Common AssociatesHide

This section is currently hidden. Click the show button to view.

Associated Minerals Based on Photo Data:

Related Minerals - Strunz-mindat GroupingHide

This section is currently hidden. Click the show button to view.

Fluorescence of Jahnsite-(NaMnMg)Hide

This section is currently hidden. Click the show button to view.

Other InformationHide

This section is currently hidden. Click the show button to view.

Notes:

At room temperature, the mineral is slowly soluble in dilute HCl.

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 Jahnsite-(NaMnMg)Hide

This section is currently hidden. Click the show button to view.

References for Jahnsite-(NaMnMg)Hide

This section is currently hidden. Click the show button to view.

Reference List:

Kampf, A. R., Elliott, P., Nash, B. P., Chiappino, L., & Varvello, S. (2018). Jahnsite-(NaMnMg), a new jahnsite-group mineral from the Sapucaia mine, Brazil and the White Rock No. 2 quarry, Australia. The Canadian Mineralogist, 56(6), 871-882.

Localities for Jahnsite-(NaMnMg)Hide

This section is currently hidden. Click the show button to view.

This map shows a selection of localities that have latitude and longitude coordinates recorded. Click on the symbol to view information about a locality. The symbol next to localities in the list can be used to jump to that position on the map.

Locality ListHide

This section is currently hidden. Click the show button to view.

- 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). Struck out - Mineral was erroneously reported from this locality. Faded * - Never found at this locality but inferred to have existed at some point in the past (e.g. from pseudomorphs).

All localities listed without proper references should be considered as questionable.