Donate now to keep alive!Help|Log In|Register|
Home PageMindat NewsThe Mindat ManualHistory of MindatCopyright StatusManagement TeamContact UsAdvertise on Mindat
Donate to MindatSponsor a PageSponsored PagesTop Available PagesMindat AdvertisersAdvertise on Mindat
What is a mineral?The most common minerals on earthMineral PhotographyThe Elements and their MineralsGeological TimeMineral Evolution
Minerals by PropertiesMinerals by ChemistryAdvanced Locality SearchRandom MineralRandom LocalitySearch by minIDLocalities Near MeSearch ArticlesSearch GlossaryMore Search Options
Search For:
Mineral Name:
Locality Name:
The Mindat ManualAdd a New PhotoRate PhotosLocality Edit ReportCoordinate Completion ReportAdd Glossary Item
StatisticsThe ElementsMember ListBooks & MagazinesMineral MuseumsMineral Shows & EventsThe Mindat DirectoryDevice Settings
Photo SearchPhoto GalleriesNew Photos TodayNew Photos YesterdayMembers' Photo GalleriesPast Photo of the Day Gallery


This page is currently not sponsored. Click here to sponsor this page.
(Ca,Mn)4Be3Si6O17(OH)4 · 3H2O
Creamy-white, light beige
Specific Gravity:
Crystal System:
Named after its discovery locality, Vevja quarry, Tvedalen area, Vestfold, Norway.
May belong to the Zeolite Group (uncertain since crystal structure has not been determined yet).

Hide all sections | Show all sections

Classification of TvedaliteHide


9 : SILICATES (Germanates)
D : Inosilicates
F : Inosilicates with 2-periodic multiple chains

70 : INOSILICATES Column or Tube Structures
5 : Column or Tube Structures with chains linked by Be

14 : Silicates not Containing Aluminum
3 : Silicates of Be

Physical Properties of TvedaliteHide

Creamy-white, light beige
4½ on Mohs scale
Hardness Data:
2.541 g/cm3 (Measured)    2.554 g/cm3 (Calculated)

Optical Data of TvedaliteHide

r > v

Chemical Properties of TvedaliteHide

(Ca,Mn)4Be3Si6O17(OH)4 · 3H2O
IMA Formula:
Ca4Be3Si6O17(OH)4 · 3H2O
Common Impurities:

Crystallography of TvedaliteHide

Crystal System:
Cell Parameters:
a = 8.72 Å, b = 23.14 Å, c = 4.92 Å
a:b:c = 0.377 : 1 : 0.213
Unit Cell V:
992.76 ų (Calculated from Unit Cell)
C-centered lattice, space group unknown

X-Ray Powder DiffractionHide

Powder Diffraction Data:
11.6 (93)
5.80 (68)
3.87 (75)
3.16 (74)
2.889 (75)
2.837 (100)
2.494 (58)

Occurrences of TvedaliteHide

Paragenetic Mode(s):

Type Occurrence of TvedaliteHide

General Appearance of Type Material:
Spherulites up to 3 mm in diameter composed of densely packed, radially oriented platelets (a few μ in length). The spherulites are overgrown by a crust of chiavennite.
Geological Setting of Type Material:
In heavily zeolitized and hydrothermally parts of irregular nepheline syenite pegmatites

Synonyms of TvedaliteHide

Other Language Names for TvedaliteHide


Common AssociatesHide

ChiavenniteCaMnBe2Si5O13(OH)2 · 2H2O
Associated Minerals Based on Photo Data:
Chiavennite3 photos of Tvedalite associated with Chiavennite on
Analcime3 photos of Tvedalite associated with Analcime on
Aegirine1 photo of Tvedalite associated with Aegirine on

Related Minerals - Nickel-Strunz GroupingHide

9.DF.05Jimthompsonite(Mg,Fe)5Si6O16(OH)2Orth. mmm (2/m 2/m 2/m) : Pbca
9.DF.15ErshoviteNa4K3(Fe,Mn,Ti)2Si8O22(OH)4 · 4H2OTric.
9.DF.15ParaershoviteNa3K3Fe3+2Si8O20(OH)4 · 4H2OTric. 1 : P1
9.DF.25BaveniteCa4Be2Al2Si9O26(OH)2Orth. mm2
9.DF.30BigcreekiteBaSi2O5 · 4H2OOrth. mmm (2/m 2/m 2/m) : Pnma

Related Minerals - Hey's Chemical Index of Minerals GroupingHide

14.3.1PhenakiteBe2SiO4Trig. 3 : R3
14.3.2BertranditeBe4(Si2O7)(OH)2Orth. mm2 : Cmc21
14.3.3BerylliteBe3(SiO4)(OH)2 · H2OOrth.
14.3.4LiberiteLi2BeSiO4Mon. m : Pm
14.3.5ChkaloviteNa2BeSi2O6Orth. mm2 : Fdd2
14.3.6EudidymiteNa2Be2Si6O15 · H2OMon. 2/m : B2/b
14.3.7EpididymiteNa2Be2Si6O15 · H2OOrth. mmm (2/m 2/m 2/m) : Pnma
14.3.10Semenovite-(Ce)Na8Ca2FeBe6Ce2Si14O40(OH)4F4Orth. mmm (2/m 2/m 2/m)
14.3.12Hingganite-(Ce)(Ce,REE)2(□,Fe2+)Be2[SiO4]2(OH)2Mon. 2/m : P21/b
14.3.14Hingganite-(Y)(Y,REE,Ca)2(□,Fe2+)Be2[SiO4]2(OH)2Mon. 2/m : P21/b
14.3.15Minasgeraisite-(Y)CaBe2Y2Si2O10Mon. 2/m : P21/b
14.3.16SørenseniteNa4SnBe2Si6O16(OH)4Mon. 2/m : B2/b
14.3.17TrimeriteCaMn2+2Be3(SiO4)3Mon. 2/m : P21/m
14.3.18ChiavenniteCaMnBe2Si5O13(OH)2 · 2H2OMon. 2/m : P21/b
14.3.21SverigeiteNaMnMgSnBe2(SiO4)3(OH)Orth. mmm (2/m 2/m 2/m) : Imma
14.3.23Gadolinite-(Y)Y2Fe2+Be2Si2O10Mon. 2/m : P21/b
14.3.24Gadolinite-(Ce)(Ce,La,Nd,Y)2Fe2+Be2Si2O10Mon. 2/m

Fluorescence of TvedaliteHide


Other InformationHide

Health Risks:
No information on health risks for this material has been entered into the database. You should always treat mineral specimens with care.

References for TvedaliteHide

Reference List:
Sort by Year (asc) | by Year (desc) | by Author (A-Z) | by Author (Z-A)
Larsen, A. O., Åsheim, A., Raade, G. & Taftø, J. (1992): Tvedalite, (Ca,Mn)4Be3Si6O17(OH)4•H2O, a new mineral from syenite pegmatite in the Oslo Region, Norway. American Mineralogist: 77: 438-443.
New Minerals (1997), New Minerals 1990-1994.
Raade, G. (1996) Minerals originally described from Norway. Including notes on type material. Norsk Bergverksmuseum Skrift: 11: 104 pp. + plates 1-7.

Internet Links for TvedaliteHide

Localities for TvedaliteHide

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 locality has map coordinates listed. - This locality has estimated coordinates. ⓘ - Click for 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 (eg from pseudomorphs.)

All localities listed without proper references should be considered as questionable.
  • Telemark
    • Porsgrunn
      • Mørje
        • Sagåsen
Larsen, A.O., Åsheim, A. and Gault, R. A. (2005): Minerals of the eudialyte group from the Sagåsen larvikite quarry, Porsgrunn, Norway. Norsk Bergverksmuseum Skrifter 30: 58-62
  • Vestfold
    • Larvik
      • Tvedalen
Nordrum, F.S. (2002): Nyfunn av mineraler i Norge 2001-2002. STEIN 29 (2): 4-10; Larsen, A. O. (ed.) (2010): The Langesundsfjord. History, geology, pegmatites, minerals. Bode Verlag Gmbh, Salzhemmendorf, Germany, 240 pp
Nordrum, F. S. (2004): Nyfunn av mineraler i Norge 2003-2004. STEIN 31 (2), 36-44; Larsen, A. O. (ed.) (2010): The Langesundsfjord. History, geology, pegmatites, minerals. Bode Verlag Gmbh, Salzhemmendorf, Germany, 240 pp
        • Tuften (Tuften 1 Quarry; Tuften 2 Quarry)
Grice, J. D., Kristiansen, R., Friis, H., Rowe, R., Poirier, G.G., Selbekk, R.S., Cooper, M.A. & Larsen, A.O. (2013): Ferrochiavennite, a new beryllium silicate zeolite from syenite pegmatites in the Larvik Plutonic Complex, Oslo region, Southern Norway. Canadian Mineralogist. 51, 286.
Larsen, A. O.; Åsheim, A.; Raade, G. & Taftø, J. (1992): Tvedalite, (Ca,Mn)4Be3Si6O17(OH)4• 3H2O, a new mineral from syenite pegmatite in the Oslo Region, Norway, American Mineralogist 77, 438-443
Mineral and/or Locality is an outreach project of the Hudson Institute of Mineralogy, a 501(c)(3) not-for-profit organization.
Copyright © and the Hudson Institute of Mineralogy 1993-2018, except where stated. relies on the contributions of thousands of members and supporters.
Privacy Policy - Terms & Conditions - Contact Us Current server date and time: February 19, 2018 07:43:08 Page generated: January 24, 2018 20:40:16
Go to top of page