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Seamanite

A valid IMA mineral species - grandfathered

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Photos of Seamanite (27)Discuss Seamanite

Seamanite Gallery Search Photos of Seamanite

Edit Seamanite Add Synonym Edit CIF structures Clear Cache

Seamanite, etc.

Bengal Mine, Cannon Mine, Stambaugh, Iron River, Iron County, Michigan, USA

Seamanite

Iron Monarch Main Pit, Iron Knob, Pastoral Unincorporated Area, South Australia, Australia

Seamanite

Chicagon mine, Bates Township, Iron County, Michigan, USA

Seamanite, etc.

Bengal Mine, Cannon Mine, Stambaugh, Iron River, Iron County, Michigan, USA

Seamanite

Iron Monarch Main Pit, Iron Knob, Pastoral Unincorporated Area, South Australia, Australia

Seamanite

Chicagon mine, Bates Township, Iron County, Michigan, USA

Seamanite, etc.

Bengal Mine, Cannon Mine, Stambaugh, Iron River, Iron County, Michigan, USA

Seamanite

Iron Monarch Main Pit, Iron Knob, Pastoral Unincorporated Area, South Australia, Australia

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About SeamaniteHide

A. E. Seaman 1858 - 1937, Professor of geology 1899 - 1936

Formula:

Mn²⁺₃[B(OH)₄](PO₄)(OH)₂

Colour:

Yellow, pink, yellow-brown; colourless in transmitted light

Lustre:

Vitreous, Sub-Vitreous

Hardness:

Specific Gravity:

3.08

Crystal System:

Orthorhombic

Name:

Named in 1930 by Edward Henry Kraus, Wyllys Arthur Seaman, and Chester Baker Slawson in honour of Arthur Edmund Seaman (29 December 1858, Casnovia, Michigan, USA - 10 July 1937, Columbus, Ohio, USA), Professor of Geology and Mineralogy, Michigan College of Mines (now Michigan Technological University) who first drew attention to the mineral.

Type Locality:

ⓘ Chicagon mine, Bates Township, Iron County, Michigan, USA

Related to Moydite-(Y) and Cahnite.

Unique IdentifiersHide

Mindat ID:

3599

Long-form identifier:

mindat:1:1:3599:2

Similar NamesHide

Heamanite-(Ce)	A valid IMA mineral species	(K_0.5Ce_0.5)TiO₃
Samaniite	A valid IMA mineral species	Cu₂Fe₅Ni₂S₈
Selmanite	A synonym of Sillimanite
Simonite	A valid IMA mineral species	TlHgAs₃S₆
Zemannite	A valid IMA mineral species	Mg_0.5ZnFe³⁺(Te⁴⁺O₃)₃ · 4.5H₂O

IMA Classification of SeamaniteHide

IMA status:

Approved, 'Grandfathered' (first described prior to 1959)

IMA Formula:

Mn²⁺₃B(PO₄)(OH)₆

First published:

1930

Type description reference:

Kraus, E. H., Seaman, W. A., Slawson, and C. B. (1930) Seamanite, a new manganese phospho-borate from Iron County, Michigan. American Mineralogist, 15 (6) 220-225

Classification of SeamaniteHide

Strunz-mindat (2026):

6.AC.65

6 : BORATES
A : Monoborates
C : B(O,OH)₄, without and with additional anions; 1(T), 1(T)+OH, etc

Dana 8th ed.:

43.4.5.1

43 : COMPOUND PHOSPHATES, ETC.
4 : Anhydrous Compound Phosphates, etc·, Containing Hydroxyl or Halogen

Hey's CIM Ref.:

10.2.4

10 : Borates with other anions
2 : Borates with phosphate or arsenate

Mineral SymbolsHide

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
Sem	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 SeamaniteHide

Lustre:

Vitreous, Sub-Vitreous

Transparency:

Transparent

Colour:

Yellow, pink, yellow-brown; colourless in transmitted light

Comment:

May show the alexandrite effect. May be rosey pink in incandescent light and tan to golden brown in daylight.

Streak:

White

Hardness:

4 on Mohs scale

Tenacity:

Brittle

Cleavage:

Distinct/Good
On {001}.

Density:

3.08 g/cm³ (Measured) 3.13 g/cm³ (Calculated)

Optical Data of SeamaniteHide

Type:

Biaxial (+)

RI values:

n_α = 1.640 n_β = 1.663 n_γ = 1.665

2V:

Measured: 40°

Birefringence:

0.025

Max. Birefringence:

δ = 0.025
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.

Thickness: 30 µm Order divisions

Rotation:

Surface Relief:

High (positive)
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.

Focus:

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.

Thickness: 30 µm

Stage rotation: 0°

Dispersion:

Optical Extinction:

Parallel, X = a; Y = b; Z = c.

Pleochroism:

Non-pleochroic

Chemistry of SeamaniteHide

Mindat Formula:

Mn²⁺₃[B(OH)₄](PO₄)(OH)₂

Element Weights:

Element	% weight
Mn	44.229 %
O	42.935 %
P	8.312 %
B	2.901 %
H	1.623 %

Calculated from ideal end-member formula.

Elements listed:

B, H, Mn, O, P - search for minerals with similar chemistry

Crystallography of SeamaniteHide

Crystal System:

Orthorhombic

Class (H-M):

mmm(2/m2/m2/m) - Dipyramidal

Space Group:

Pnma

Setting:

Pbnm

Cell Parameters:

a = 7.81 Å, b = 15.11 Å, c = 6.69 Å

Ratio:

a:b:c = 0.517 : 1 : 0.443

Unit Cell V:

789.48 Å³ (Calculated from Unit Cell)

Morphology:

Crystals rod-like to acicular [001]. Acicular crystals consisting of the prism, m, and the unit bipyramid, o. The prism faces may be rough and rounded and striated along the length.

Crystal StructureHide

Load
Unit Cell | Unit Cell Packed
2x2x2 | 3x3x3 | 4x4x4

View
CIF File Best | x | y | z | a | b | c

Rotation
Stop | Start

Labels
Console Off | On | Grey | Yellow

Data courtesy of the American Mineralogist Crystal Structure Database. Click on an AMCSD ID to view structure

ID	Species	Reference	Link	Year	Locality	Pressure (GPa)	Temp (K)
0005774	Seamanite	Huminicki D M C, Hawthorne F C (2002) Hydrogen bonding in the crystal structure of seamanite The Canadian Mineralogist 40 923-928		2002		0	293
0000258	Seamanite	Moore P B, Ghose S (1971) A novel face-sharing octahedral trimer in the crystal structure of seamanite American Mineralogist 56 1527-1538		1971		0	293

CIF Raw Data - click here to close

data_global
_chemical_name_mineral 'Seamanite'
loop_
_publ_author_name
'Huminicki D M C'
'Hawthorne F C'
_journal_name_full 'The Canadian Mineralogist'
_journal_volume 40 
_journal_year 2002
_journal_page_first 923
_journal_page_last 928
_publ_section_title
;
 Hydrogen bonding in the crystal structure of seamanite
;
_database_code_amcsd 0005774
_chemical_formula_sum 'Mn3 P B O10 H6'
_cell_length_a 7.8231
_cell_length_b 15.1405
_cell_length_c 6.6999
_cell_angle_alpha 90
_cell_angle_beta 90
_cell_angle_gamma 90
_cell_volume 793.574
_exptl_crystal_density_diffrn      3.119
_symmetry_space_group_name_H-M 'P b n m'
loop_
_space_group_symop_operation_xyz
  'x,y,z'
  'x,y,1/2-z'
  '-x,-y,1/2+z'
  '1/2+x,1/2-y,1/2+z'
  '1/2-x,1/2+y,1/2-z'
  '1/2-x,1/2+y,z'
  '1/2+x,1/2-y,-z'
  '-x,-y,-z'
loop_
_atom_site_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_occupancy
_atom_site_U_iso_or_equiv
Mn(1)   0.27819   0.47584   0.25000   1.00000   0.01140
Mn(2)   0.35076   0.64067   0.50166   1.00000   0.01160
P   0.69328   0.55408   0.25000   1.00000   0.00720
B   0.00710   0.31510   0.25000   1.00000   0.01100
O(1)   0.46080   0.36880   0.25000   1.00000   0.01350
O(2)   0.18660   0.61620   0.25000   1.00000   0.01350
O(3)   0.03930   0.40940   0.25000   1.00000   0.01480
O(4)  -0.18460   0.30270   0.25000   1.00000   0.01210
O(5)   0.08120   0.27330   0.07340   1.00000   0.01590
O(6)   0.72440   0.49640   0.06460   1.00000   0.01790
O(7)   0.50400   0.58460   0.25000   1.00000   0.01360
O(8)   0.81100   0.63480   0.25000   1.00000   0.01290
H(1)   0.39900   0.31400   0.21800   0.50000   0.04360
H(2)   0.06100   6.62100   0.25000   1.00000   0.03910
H(3)  -0.04100   0.44600   0.32700   0.50000   0.04580
H(4)  -0.21600   0.24000   0.25000   1.00000   0.07130
H(5)   0.10100   0.31700  -0.03100   1.00000   0.05610
loop_
_atom_site_aniso_label
_atom_site_aniso_U_11
_atom_site_aniso_U_22
_atom_site_aniso_U_33
_atom_site_aniso_U_12
_atom_site_aniso_U_13
_atom_site_aniso_U_23
Mn(1) 0.01280 0.01120 0.01030 0.01140 0.00050 0.00000
Mn(2) 0.01430 0.01120 0.00930 0.01160 0.00030 0.00040
P 0.00780 0.00690 0.00780 0.00720 -0.00060 0.00000
B 0.00990 0.00910 0.01390 0.01100 -0.00030 0.00000
O(1) 0.01260 0.01320 0.01450 0.01350 -0.00020 0.00000
O(2) 0.01060 0.01720 0.01280 0.01350 -0.00320 0.00000
O(3) 0.02080 0.01220 0.01150 0.01480 0.00190 -0.00220
O(4) 0.01020 0.01020 0.01580 0.01210 0.00120 0.00930
O(5) 0.01130 0.00900 0.02750 0.01590 0.00020 0.00230
O(6) 0.02470 0.01310 0.01600 0.01790 0.00500 0.00320
O(7) 0.01540 0.01100 0.01430 0.01360 0.00310 -0.00090
O(8) 0.01050 0.01510 0.01300 0.01290 -0.00050 0.01210

X-Ray Powder DiffractionHide

Powder Diffraction Data:

d-spacing	Intensity
7.55 Å	(60)
6.92 Å	(100)
4.20 Å	(60)
3.78 Å	(70)
3.47 Å	(60)
2.84 Å	(80)
2.50 Å	(70)
2.39 Å	(60)

Comments:

ICDD 25-536.

Geological EnvironmentHide

Paragenetic Mode(s):

Paragenetic Mode	Earliest Age (Ga)
Stage 7: Great Oxidation Event	<2.4
47a : [Near-surface hydration of prior minerals]
47c : [Carbonates, phosphates, borates, nitrates]
47e : [Vanadates, chromates, manganates]

Type Occurrence of SeamaniteHide

Type Locality:

ⓘ Chicagon mine, Bates Township, Iron County, Michigan, USA

General Appearance of Type Material:

Small acicular crystals up to 10 x 2 x 1 millimeters in size.

Place of Conservation of Type Material:

Michigan Technical University, Houghton, Michigan, USA.
National Museum of Natural History, Washington, D.C., USA, 96282.

Geological Setting of Type Material:

In crevices of a badly fractured and highly ferruginous siliceous rock.

Associated Minerals at Type Locality:

Calcite

Shigaite

Sussexite

Reference:

Kraus, E. H., Seaman, W. A., Slawson, and C. B. (1930) Seamanite, a new manganese phospho-borate from Iron County, Michigan. American Mineralogist, 15 (6) 220-225

Other Language Names for SeamaniteHide

Dutch:Seamaniet

German:Seamanit

Russian:Симанит

Simplified Chinese:磷硼锰石

Spanish:Seamanita

Traditional Chinese:磷硼錳石

Common AssociatesHide

Associations Based on Photo Data:

14 photos of Seamanite associated with Shigaite	Mn₆Al₃(OH)₁₈[Na(H₂O)₆](SO₄)₂ · 6H₂O
6 photos of Seamanite associated with Triploidite	Mn²⁺₂(PO₄)(OH)
5 photos of Seamanite associated with Hematite	Fe₂O₃
3 photos of Seamanite associated with Rhodochrosite	MnCO₃
1 photo of Seamanite associated with 'Limonite'
1 photo of Seamanite associated with Calcite	CaCO₃

Related Minerals - Strunz-mindat Grouping Hide

6.AC.05	Sinhalite	MgAl(BO₄)	Orth. mmm(2/m2/m2/m) : Pnma
6.AC.10	Pseudosinhalite	Mg₂Al₃(BO₃)₂(OH)O₃	Mon. 2/m : P2₁/c
6.AC.15	Béhierite	Ta(BO₄)	Tet. 4/mmm(4/m2/m2/m) : I4₁/amd
6.AC.15	Schiavinatoite	Nb(BO₄)	Tet. 4/mmm(4/m2/m2/m) : I4₁/amd
6.AC.20	Frolovite	Ca[B(OH)₄]₂	Tric. 1 : P1
6.AC.25	Hexahydroborite	Ca[B(OH)₄]₂ · 2H₂O or CaB₂O₄ · 6H₂O	Mon. 2/m : B2/b
6.AC.30	Henmilite	Ca₂Cu[B(OH)₄]₂(OH)₄	Tric. 1 : P1
6.AC.35	Bandylite	Cu[B(OH)₄]Cl	Tet. 4/mmm(4/m2/m2/m) : P4/nmm
6.AC.40	Teepleite	Na₂[B(OH)₄]Cl	Tet. 4/mmm(4/m2/m2/m) : P4/nmm
6.AC.45	Moydite-(Y)	Y[B(OH)₄](CO₃)	Orth. mmm(2/m2/m2/m) : Pbca
6.AC.50	Carboborite	Ca₂Mg[B(OH)₄]₂(CO₃)₂ · 4H₂O	Mon. 2/m : P2₁/c
6.AC.55	Sulfoborite	Mg₃[B(OH)₄]₂(SO₄)(OH,F)₂	Orth. mmm(2/m2/m2/m) : Pnma
6.AC.60	Lüneburgite	Mg₃[B₂(OH)₆](PO₄)₂ · 6H₂O	Tric. 1 : P1
6.AC.70	Cahnite	Ca₂[B(OH)₄](AsO₄)	Tet. 4 : P4

Fluorescence of SeamaniteHide

In UV light:

Not fluorescent in UV.

Other InformationHide

Thermal Behaviour:

Before the blowpipe, fuses easily, after losing its water, to a dark slag.

Notes:

Soluble in cold, dilute acids.

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 SeamaniteHide

mindat.org URL:

https://www.mindat.org/min-3599.html
Please feel free to link to this page.

Search Engines:

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Look for Seamanite in the Rock H. Currier Digital Library

External Links:

Look for Seamanite on Webmineral

Look for Seamanite on Wikipedia

Look for Seamanite on Mineralien Atlas

Raman and XRD data at RRUFF project

References and PDF downloads at RRUFF project

American Mineralogist Crystal Structure Database

Handbook of Mineralogy page PDF

Mineral Dealers:

Buy from D. Joyce minerals

References for SeamaniteHide

Reference List:

Kraus, E. H., Seaman, W. A., Slawson, and C. B. (1930) Seamanite, a new manganese phospho-borate from Iron County, Michigan. American Mineralogist, 15 (6) 220-225

McConnell, Duncan, Pondrom, Walter L. (1941) X-ray crystallography of seamanite. American Mineralogist, 26 (7) 446-447

Palache, Charles; Berman, Harry; Frondel, Clifford (1951) The System of Mineralogy (7th ed.) Vol. 2 - Halides, Nitrates, Borates, Carbonates, Sulfates, Phosphates, Arsenates, Tungstates, Molybdates, Etc. John Wiley and Sons.pp.388-389

Kurkutova, E.N., Rau, V.G., Rumanova, I.M. (1971) Crystalline structure of seamanite Mn3[PO4/BO3]·3H2O = Mn3[PO3OH][BO(OH)3](OH)2. Soviet Physics - Doklady: 16: 272-274.

Moore, Paul B., Ghose, Subrata (1971) A novel face-sharing octahedral trimer in the crystal structure of seamanite. American Mineralogist, 56 (9-10) 1527-1538

Grew, Edward S.; Anovitz, Lawrence M. - Eds. (1996) Boron - Mineralogy, Petrology and Geochemistry. Reviews in Mineralogy Vol. 33. Mineralogical Society of America p.862

Huminicki, D. M.C., Hawthorne, F. C. (2002) Hydrogen bonding in the crystal structure of seamanite. The Canadian Mineralogist, 40 (3) 923-928 doi:10.2113/gscanmin.40.3.923

(2005) Seamanite. Handbook of Mineralogy. Mineralogical Society of America

Localities for SeamaniteHide

Showing 6 localities.

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.

Hide all sections | Show all sections

Locality ListHide

- 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.


Australia
South Australia Pastoral Unincorporated Area Iron Knob ⓘ Iron Monarch Main Pit	Pring et al. (2000)

USA (TL)
Michigan Iron County Bates Township ⓘ Chicagon mine (TL)	Kraus et al. (1930) +1 other reference
Iron River Mineral Hills Homer-Wauseca Group ⓘ Homer Mine	Travis Olds collection
Stambaugh ⓘ Cannon Mine (Bengal-Tully Mine)	Heinrich et al. (2004)
ⓘ Bengal Mine (Bangal Mine)	Heinrich et al. (2004)
Marquette County Negaunee ⓘ Cambria-Jackson Mine	Heinrich et al. (2004)

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Seamanite

About SeamaniteHide

Unique IdentifiersHide

Similar NamesHide

IMA Classification of SeamaniteHide

Classification of SeamaniteHide

Mineral SymbolsHide

Physical Properties of SeamaniteHide

Optical Data of SeamaniteHide

Chemistry of SeamaniteHide

Crystallography of SeamaniteHide

Crystal StructureHide

X-Ray Powder DiffractionHide

Geological EnvironmentHide

Type Occurrence of SeamaniteHide

Other Language Names for SeamaniteHide

Common AssociatesHide

Related Minerals - Strunz-mindat GroupingHide

Fluorescence of SeamaniteHide

Other InformationHide

Internet Links for SeamaniteHide

References for SeamaniteHide

Localities for SeamaniteHide

Locality ListHide

Related Minerals - Strunz-mindat Grouping Hide