Mindat Logo
Home Page Log In Message Board The Mindat Directory
Register Search Pages Chat Now! (2 online) Mindat Auctions

Boltwoodite

Big Photo

Rössing Mine, Arandis, Swakopmund District, Erongo Region, Namibia
© Stephan Wolfsried

Show Boltwoodite Photos (83)
Formula:
(K,Na)(UO
 
2
)[HSiO
 
4
] · 0.5H
 
2
O
System:MonoclinicColour:Pale yellow, orange ...
Lustre:Sub-Vitreous, Waxy, SilkyHardness:3½ - 4
Name:
For Bertram Borden Boltwood (1870-1927), radiochemist at Yale University, New Haven, Connecticut, USA. Named by Clifford Frondel and Jun Ito.
Isostructural with:Uranophane Group


Rod-like to acicular yellow crystals in radial groups

Classification of Boltwoodite

IMA status:Valid - first described prior to 1959 (pre-IMA) - "Grandfathered"
Strunz 8th edition ID:8/B.34-60
Nickel-Strunz 10th (pending) edition ID:9.AK.15

9 : SILICATES (Germanates)
A : Nesosilicates
K : Uranyl neso- and polysilicates
Dana 8th edition ID:53.3.1.5

53 : NESOSILICATES Insular SiO4 Groups and Other Anions or Complex Cations
3 : Insular SiO4 Groups and Other Anions of Complex Cations with (UO2)
Hey's CIM Ref.:14.16.6

14 : Silicates not Containing Aluminum
16 : Silicates of U
mindat.org URL:http://www.mindat.org/min-716.html
Please feel free to link to this page.

Type Occurrence of Boltwoodite

Type Locality:Pick's Delta Mine (Delta Mine; Pick's Mine), Delta, San Rafael District (San Rafael Swell), Emery Co., Utah, USA
Year of Discovery:1956

Occurrences of Boltwoodite

Geological Setting:Alteration zone around uranium deposits.

Physical Properties of Boltwoodite

Lustre:Sub-Vitreous, Waxy, Silky
Diaphaneity (Transparency):Translucent
Comment:Aggregates vitreous to silky, dull to earthy in pseudomorphs
Colour:Pale yellow, orange yellow
Streak:White
Hardness (Mohs):3½ - 4
Tenacity:Brittle
Cleavage:Perfect
Perfect on {010}
imperfect on {001}
Fracture:Irregular/Uneven
Density (measured):4.7 g/cm3
Density (calculated):4.46 g/cm3

Crystallography of Boltwoodite

Crystal System:Monoclinic
Class (H-M):2 - Sphenoidal
Space Group:P21 {P1 1 21} {P21} {P1 21 1}
Cell Parameters:a = 7.073(2) Å, b = 7.064(1) Å, c = 6.638(1) Å
β = 105.45°
Ratio:a:b:c = 1.001 : 1 : 0.94
Unit Cell Volume:V 319.67 ų (Calculated from Unit Cell)
Z:2
Morphology:Radiating acicular to fibrous crystals, also earthy pseudomorphs of uranium minerals
X-Ray Powder Diffraction:
d-spacingIntensity
6.81 (10)
6.40 (50)
3.54 (70)
3.40 (90)
2.95 (80)
2.91 (70)
1.900 (60)
1.764 (60)
Comments:35-490

Optical Data of Boltwoodite

Type:Biaxial (-)
RI values: nα = 1.668 - 1.670 nβ = 1.695 - 1.696 nγ = 1.698 - 1.703
Birefringence:0.007-0.008
Maximum Birefringence:δ = 0.030 - 0.033

Chart shows birefringence interference colour range (at 30µm thickness) and does not take into account mineral colouration.
Surface Relief:High
Dispersion:r > v or r < v
Pleochroism:Weak
Comments:X= colorless
Y=Z= yellow

Chemical Properties of Boltwoodite

Formula:
(K,Na)(UO
 
2
)[HSiO
 
4
] · 0.5H
 
2
O
Essential elements:H, K, O, Si, U
All elements listed in formula:H, K, Na, O, Si, U
Common Impurities:Fe,Ca,Na

Relationship of Boltwoodite to other Species

Member of Group:
Uranophane Group:
Related Minerals - Nickel-Strunz Grouping):

- +
9.AK.05Soddyite
(UO
 
2
)
 
2
SiO
 
4
·2H
 
2
O
9.AK.10Cuprosklodowskite
Cu(UO
 
2
)
 
2
[HSiO
 
4
]
 
2
 · 6H
 
2
O
9.AK.10Oursinite
(Co,Mg)(UO
 
2
)
 
2
[HSiO
 
4
]
 
2
 · 6H
 
2
O
9.AK.10Sklodowskite
Mg(UO
 
2
)
 
2
[HSiO
 
4
]
 
2
 · 5H
 
2
O
9.AK.15Kasolite
Pb(UO
 
2
)[SiO
 
4
] · H
 
2
O
9.AK.15Natroboltwoodite
(H
 
3
O)(Na,K)UO
 
2
SiO
 
4
·H
 
2
O
9.AK.15Uranophane
Ca(UO
 
2
)
 
2
[HSiO
 
4
]
 
2
 · 5H
 
2
O
9.AK.15Beta-Uranophane
9.AK.20Swamboite
UH
 
6
(UO
 
2
)
 
6
(SiO
 
4
)
 
6
·30H
 
2
O
9.AK.25Haiweeite
Ca(UO
 
2
)
 
2
[Si
 
5
O
 
12
(OH)
 
2
]·4.5H
 
2
O
9.AK.25Metahaiweeite
Ca(UO
 
2
)
 
2
Si
 
6
O
 
15
·nH
 
2
O
9.AK.25Ranquilite
9.AK.30Weeksite
K
 
2
(UO
 
2
)
 
2
(Si
 
2
O
 
5
)
 
3
·4H
 
2
O
9.AK.30Coutinhoite
Th
 
x
Ba
 
(1-2x)
(UO
 
2
)
 
2
Si
 
5
O
 
13
·(H
 
2
O)
 
1+y
 (0 < x < 0.5 and 0 < y < (2+x))
9.AK.35Ursilite
(Mg,Ca)
 
4
(UO
 
2
)
 
4
(Si
 
2
O
 
5
)
 
5.5
(OH)
 
5
·13H
 
2
O
9.AK.35Magnioursilite
Mg
 
4
(UO
 
2
)
 
4
(Si
 
2
O
 
5
)
 
5
(OH)
 
6
·20H
 
2
O
9.AK.35Calcioursilite
Ca
 
4
(UO
 
2
)
 
4
(Si
 
2
O
 
5
)
 
5
(OH)
 
6
·15H
 
2
O
9.AK.40Uranosilite
UO
 
3
 · 7SiO
 
2
Related Minerals - Hey's Index Grouping:

- +
14.16.1Uranosilite
UO
 
3
 · 7SiO
 
2
14.16.2Coffinite
(U,Th)[(OH)
 
4x
|(SiO
 
4
)
 
1-x
]
14.16.3Soddyite
(UO
 
2
)
 
2
SiO
 
4
·2H
 
2
O
14.16.4Swamboite
UH
 
6
(UO
 
2
)
 
6
(SiO
 
4
)
 
6
·30H
 
2
O
14.16.5Weeksite
K
 
2
(UO
 
2
)
 
2
(Si
 
2
O
 
5
)
 
3
·4H
 
2
O
14.16.7Natroboltwoodite
(H
 
3
O)(Na,K)UO
 
2
SiO
 
4
·H
 
2
O
14.16.8Cuprosklodowskite
Cu(UO
 
2
)
 
2
[HSiO
 
4
]
 
2
 · 6H
 
2
O
14.16.9Sklodowskite
Mg(UO
 
2
)
 
2
[HSiO
 
4
]
 
2
 · 5H
 
2
O
14.16.10Uranophane
Ca(UO
 
2
)
 
2
[HSiO
 
4
]
 
2
 · 5H
 
2
O
14.16.11β-Uranophane
Ca(UO
 
2
)
 
2
[HSiO
 
4
]
 
2
 · 5H
 
2
O
14.16.12Haiweeite
Ca(UO
 
2
)
 
2
[Si
 
5
O
 
12
(OH)
 
2
]·4.5H
 
2
O
14.16.13Metahaiweeite
Ca(UO
 
2
)
 
2
Si
 
6
O
 
15
·nH
 
2
O
14.16.14Thorogummite
(Th,U)[(OH)
 
4x
|(SiO
 
4
)
 
1-x
]
14.16.15Steacyite
([ ],K)(Na,Ca)
 
2
(Th,U)[Si
 
8
O
 
20
]
14.16.16Ekanite
(Ca,Fe
2+
 
,Pb)
 
2
(Th,U)[Si
 
8
O
 
20
]
14.16.17Kasolite
Pb(UO
 
2
)[SiO
 
4
] · H
 
2
O
14.16.18 Orlite
Pb
 
3
(UO
 
2
)
 
3
(Si
 
2
O
 
7
)
 
2
·6H
 
2
O
14.16.19Oursinite
(Co,Mg)(UO
 
2
)
 
2
[HSiO
 
4
]
 
2
 · 6H
 
2
O

Other Names for Boltwoodite

Other Languages:
German:Boltwoodit
Russian:Болтвудит
Spanish:Boltwoodita

Other Information

Health Warning:Contains uranium - always wash hands after handling. Avoid inhaling dust when handling or breaking. Never lick or ingest. Avoid prolonged exposure in proximity of the body. Store away from inhabited areas.

References for Boltwoodite

Reference List:American Mineralogist: 46: 12-25.

American Mineralogist: 66: 610-625.

Burns, P.C. (1998) The structure of boltwoodite and implications of solid-solution towards sodium boltwoodite. Canadian Mineralogist: 36: 1069-1075.

Burns, P.C. (2005) U 6+ minerals and inorganic compounds: insights into an expanded structural hierarchy of crystal structures. Canadian Mineralogist: 43: 1839-1894.

Internet Links for Boltwoodite

Search Engines:
  • Look for Boltwoodite on Google
  • Look for Boltwoodite images on Google
    • External Links:
  • Look for Boltwoodite on Webmineral
  • Look for Boltwoodite on Athena Mineralogy
  • Look for Boltwoodite on Wikipedia
  • Look for Boltwoodite on Mineralien Atlas
  • Raman and XRD data at RRUFF project
  • American Mineralogist Crystal Structure Database
  • Search for Boltwoodite in the Natural History Museum (London) online catalogue
  • Boltwoodite details from Handbook of Mineralogy (PDF)
    • Mineral Dealers:
  • SpiriferMinerals.com - high quality specimens
  • Buy from David K Joyce minerals
  • Fine Minerals from Dan Weinrich Minerals
  • Buy Minerals and Crystals from Crystalarium.com
  • Buy Fine Minerals from mineralsweb.com
  • Buy fine minerals and gemstones from Pala International
  • Search for - Boltwoodite - on e-Rocks Mineral Sales & Auctions
  • Top quality minerals from Kristalle of California
  • rare and unusual minerals mainly crystallized
  • Rare and Unusual minerals at Mineralogical Research Company
  • High-end worldwide specimens & outstanding customer service
  • Find Boltwoodite on www.crystalclassics.co.uk
    • Jobs:
  • Mining & Geology Jobs

    • Page Sponsor

    Sponsorship:This page is currently not sponsored. Click here to sponsor this page.

    Localities for Boltwoodite

    Hide Locality List
    The 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.
    (TL) indicates type locality. ? indicates mineral may be doubtful at this locality. All other localities listed without reference should be considered as uncertain and unproven until references can be found.
    Argentina
     
    • Córdoba
      • Quebrada del Tigre
    		American Mineralogist: 46: 12-25.
    • La Rioja
    		American Mineralogist: 46: 12-25.
    Australia
     
    • South Australia
      • Flinders Ranges
        • North Flinders Ranges
          • Mt Painter area
            • Radium Ridge
    		2003, Brugger, J., Ansermet, S. & Pring, A. ' Uranium minerals from Mt Painter, Northern Flinders ranges, South Australia' Australian Journal of Mineralogy, vol. 9, n°1, pp 15-31
      • Mt Lofty Ranges
        • South Mt Lofty Ranges
          • Fleurieu Peninsula
            • Myponga
    		American Mineralogist: 46: 12-25.
    Czech Republic
     
    • Bohemia (Böhmen; Boehmen)
      • Karlovy Vary Region
        • Krušné Hory Mts (Erzgebirge)
          • Ostrov
    		Pauliš P., Kopecký S., Černý P. 2007: Uranové minerály České Republiky a jejich naleziště. 1. část. (Kutna Hora, issue 1)
    • Moravia (Mähren; Maehren)
      • Vysočina Region
        • Žďár nad Sázavou
    		Pauliš P., Kopecký S., Černý P. 2007: Uranové minerály České Republiky a jejich naleziště. 1. část. (Kutna Hora, issue 1)
    France
     
    • Limousin
      • Haute-Vienne
        • Mailhac
    		Le Règne Minéral, Hors Série IV, 1998
    Germany
     
    • Rhineland-Palatinate
      • Hunsrück Mts
        • Birkenfeld
          • Ellweiler
    		Aufschluss 69/(7+8), Lapis 79/(7+8)
    • Saxony
      • Vogtland
        • Falkenstein
          • Bergen
    		Wittern: "Mineralfundorte in Deutschland", 2001
    Japan
     
    • Honshu Island
      • Chugoku Region
        • Tottori Prefecture
    		K. Watanabe (1976) Journal of the Faculty of Science, Shinshu University, 11, 53-113 (in japanese with english summary)
          • Tohgoh-cho
    		Watanabe (1976) Journal of the Faculty of Science, Shinshu University, 11, 53-106.
    Mexico
     
    • Chihuahua
      • Mun. de Aldama
        • Peña Blanca District
          • Sierra Peña Blanca
    		http://www.swri.org/4org/d20/ghs/PBlanca/mineral.html
    Namibia
     
    • Erongo Region
      • Swakopmund District
    T. Kennedy collection
    Rafael Hernandes Corrêa-Silva.
    Am.Min.: 84:993.
    Norway
     
    • Nordland
      • Tysfjord
    		Eldjarn, K.(1988). Etter Neumann. NAGS-nytt 15 (1-4),62 (in norwegian)
    South Africa
     
    • Western Cape Province
    		Minerals of South Africa
    Sweden
     
    • Jämtland
      • Krokom
    • Lappland
      • Arjeplog
    • Medelpad
      • Ånge
    UK
     
    • England
      • Cornwall
        • St Just District
          • Botallack - Pendeen Area
            • Botallack
    		[Journal of the Russell Society, 6(1), 17-26 (1995)]
    USA
     
    • Arizona
      • Coconino Co.
        • Cameron District
    		Anthony, J.W., et al (1995), Mineralogy of Arizona, 3rd.ed.: 141.
            • Huskon Mines
    		Anthony, J.W., et al (1995), Mineralogy of Arizona, 3rd.ed.: 141; Daphne Ross cited in Honea, R.M. (1961), New data on boltwoodite, an alkali uranyl silicate, Am.Min.: 46: 24.
    Anthony, J.W., et al (1995), Mineralogy of Arizona, 3rd.ed.: 141; Daphne Ross cited in Honea, R.M. (1961), New data on boltwoodite, an alkali uranyl silicate, Am.Min.: 46: 24.
    Anthony, J.W., et al (1995), Mineralogy of Arizona, 3rd.ed.: 181.
    Anthony, J.W., et al (1995), Mineralogy of Arizona, 3rd.ed.: 141; Austin, S.R. (1964), Mineralogy of the Cameron area, Coconino Co., AZ, US Atomic Energy Comm. RME 99, Tech. Inf. Serv., Oak Ridge, TN: 99.
          • Cameron area
    		Anthony, J.W., et al (1995), Mineralogy of Arizona, 3rd.ed.: 141; Austin, S.R. (1964), Mineralogy of the Cameron area, Coconino Co., AZ, US Atomic Energy Comm. RME 99, Tech. Inf. Serv., OAk Ridge, TN: 99.
    Anthony, J.W., et al (1995), Mineralogy of Arizona, 3rd.ed.: 141; Austin, S.R. (1964), Mineralogy of the Cameron area, Coconino Co., AZ, US Atomic Energy Comm. RME 99, Tech. Inf. Serv., Oak Ridge, TN: 99.
    • California
      • San Bernardino Co.
        • Bristol Mts
          • Amboy
    		 Murdoch, Joseph & Robert W. Webb (1966), Minerals of California, Centennial Volume (1866-1966): California Division Mines & Geology Bulletin 189: 108; Pemberton, H. Earl (1983), Minerals of California; Van Nostrand Reinholt Press: 517.
    • Colorado
      • Gunnison Co.
        • Marshall Pass District
    		Minerals of Colorado (1997) Eckels, E. B.
      • Saguache Co.
        • Marshall Pass District
    		Minerals of Colorado (1997) Eckel, E. B.; Am Min 50:909-923
    • Nevada
      • Clark Co.
        • Goodsprings District
    		Rocks & Minerals, Nov. 1999
    • Pennsylvania
      • Northampton Co.
        • Forks Township
          • Easton
    		Lapham & Geyer, 1965. Mineral Collecting in Pennsylvania
    American Mineralogist: 46: 12-25.; Am.Min.: 45: 39-52
    • Texas
      • Live Oak Co.
    		R&M 66:3 pp 196-224
    • Utah
      • Emery Co.
        • San Rafael District (San Rafael Swell)
          • Delta
    		[Nickel & Nichols, 1991 - "Mineral Reference Manual, p25]
    U.S. Geological Survey, 2005, Mineral Resources Data System: U.S. Geological Survey, Reston, Virginia.
    UGMS Bull 117 Minerals and Mineral Localities of Utah
      • Grand Co.
        • Seven Mile District
    		UGMS Bull 117 Minerals and Mineral Localities of Utah
      • Juab Co.
        • Honeycomb Hills
    		Rocks & Minerals: 68(6): 381-393.
      • San Juan Co.
        • Blanding
    		Mineralogical Record: 22(5): 381-393.
    UGMS Bull 117 Minerals and Mineral Localities of Utah
    UGMS Bull 117 Minerals and Mineral Localities of Utah
        • Montezuma Canyon
    		UGMS Bull 117 Minerals and Mineral Localities of Utah
        • White Canyon District
          • Red Canyon
    		UGMS Bull 117 Minerals and Mineral Localities of Utah
          • White Canyon
            • Copper Point
    		American Mineralogist: 46: 12-25.
    Min Rec 30 pp231-238
    • Wyoming
      • Big Horn Co.
        • Little Mountain District
    		American Mineralogist: 46: 12-25.
      • Niobrara Co.
        • Lance Creek
    		American Mineralogist: 46: 12-25.
    Mineral and/or Locality
    Google
     
    www.mindat.org Web
    Copyright © Jolyon Ralph and Ida Chau 1993-2009. Site Map. Locality, mineral & photograph data are the copyright of the individuals who submitted them.Further information contact the Site hosted & developed by Jolyon Ralph. Mindat.org is an online information resource dedicated to providing free mineralogical information to all. Mindat relies on the contributions of hundreds of members and supporters. If you would like to add information to improve the quality of our database, then click here to register. Current server date and time: 1st Nov 2009 18:11:12