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Thornasite

A valid IMA mineral species

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Photos of Thornasite (21)

Thornasite Gallery Search Photos of Thornasite

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Thornasite

Demix-Varennes quarry, Saint-Amable sill, Varennes & St-Amable, Lajemmerais RCM, Montérégie, Québec, Canada

Thornasite

Demix-Varennes quarry, Saint-Amable sill, Varennes & St-Amable, Lajemmerais RCM, Montérégie, Québec, Canada

Thornasite

Demix-Varennes quarry, Saint-Amable sill, Varennes & St-Amable, Lajemmerais RCM, Montérégie, Québec, Canada

Thornasite

Demix-Varennes quarry, Saint-Amable sill, Varennes & St-Amable, Lajemmerais RCM, Montérégie, Québec, Canada

Thornasite

Demix-Varennes quarry, Saint-Amable sill, Varennes & St-Amable, Lajemmerais RCM, Montérégie, Québec, Canada

Thornasite

Demix-Varennes quarry, Saint-Amable sill, Varennes & St-Amable, Lajemmerais RCM, Montérégie, Québec, Canada

Thornasite

Demix-Varennes quarry, Saint-Amable sill, Varennes & St-Amable, Lajemmerais RCM, Montérégie, Québec, Canada

Thornasite

Demix-Varennes quarry, Saint-Amable sill, Varennes & St-Amable, Lajemmerais RCM, Montérégie, Québec, Canada

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About ThornasiteHide

Formula:

(Na,K)₁₂Th₃[Si₈O₁₉]₄ · 18H₂O

Colour:

Light green to beige

Lustre:

Vitreous, Waxy, Greasy, Pearly

Specific Gravity:

2.62

Crystal System:

Trigonal

Name:

The name reflects its composition: thorium (Thor), sodium (Na) and silicon (Si).

Type Locality:

ⓘ Poudrette quarry (De-Mix quarry; Demix quarry; Uni-Mix quarry; Carrière Mont Saint-Hilaire; MSH), Mont Saint-Hilaire, La Vallée-du-Richelieu RCM, Montérégie, Québec, Canada

This page provides mineralogical data about Thornasite.

Unique IdentifiersHide

Mindat ID:

3947

Long-form identifier:

mindat:1:1:3947:1

GUID
(UUID V4):

0f91a412-3fc5-48a1-bf83-563c620228bc

IMA Classification of ThornasiteHide

IMA status:

Approved

IMA Formula:

Na₁₂Th₃(Si₈O₁₉)₄ · 18H₂O

Approval year:

1985

First published:

1987

Classification of ThornasiteHide

Strunz-mindat (2024):

9.GF.50

9 : SILICATES (Germanates)
G : Tektosilicates with zeolitic H₂O; zeolite family
F : Other Rare Zeolites

Dana 8th ed.:

72.1.2.1

72 : PHYLLOSILICATES Two-Dimensional Infinite Sheets with Other Than Six-Membered Rings
1 : Two-Dimensional Infinite Sheets with Other Than Six-Membered Rings with 4-membered rings

Hey's CIM Ref.:

14.11.4

14 : Silicates not Containing Aluminum
11 : Silicates of Th and Hg

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
Tna	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 ThornasiteHide

Lustre:

Vitreous, Waxy, Greasy, Pearly

Transparency:

Transparent, Translucent, Opaque

Colour:

Light green to beige

Streak:

White

Hardness Data:

Could not be measured

Comment:

Could not be measured due to the small crystal size and brittleness.

Tenacity:

Brittle

Fracture:

Irregular/Uneven, Sub-Conchoidal

Density:

2.62(2) g/cm³ (Measured) 2.627 g/cm³ (Calculated)

Optical Data of ThornasiteHide

Type:

Uniaxial (+)

RI values:

n_ω = 1.510(1) n_ε = 1.512(1)

Max Birefringence:

δ = 0.002

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

Surface Relief:

Low

Chemistry of ThornasiteHide

Mindat Formula:

(Na,K)₁₂Th₃[Si₈O₁₉]₄ · 18H₂O

Elements listed:

H, K, Na, O, Si, Th - search for minerals with similar chemistry

Common Impurities:

U,Al,Ca,Cl

Crystallography of ThornasiteHide

Crystal System:

Trigonal

Class (H-M):

3m - Ditrigonal Pyramidal

Space Group:

R3m

Setting:

R3m

Cell Parameters:

a = 29.08 Å, c = 17.30 Å

Ratio:

a:c = 1 : 0.595

Unit Cell V:

12,669.68 Å³ (Calculated from Unit Cell)

Crystal StructureHide

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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)
0002591	Thornasite	Li Y, Krivovichev S V, Burns P C (2000) The crystal structure of thornasite: A novel interrupted silicate framework American Mineralogist 85 1521-1525		2000		0	293

CIF Raw Data - click here to close

data_global
_chemical_name_mineral 'Thornasite'
loop_
_publ_author_name
'Li Y'
'Krivovichev S V'
'Burns P C'
_journal_name_full 'American Mineralogist'
_journal_volume 85 
_journal_year 2000
_journal_page_first 1521
_journal_page_last 1525
_publ_section_title
;
 The crystal structure of thornasite: A novel interrupted silicate framework
;
_database_code_amcsd 0002591
_chemical_formula_sum 'Th3 Si32 Na12 O94 H36'
_cell_length_a 29.124
_cell_length_b 29.124
_cell_length_c 17.2602
_cell_angle_alpha 90
_cell_angle_beta 90
_cell_angle_gamma 120
_cell_volume 12678.810
_exptl_crystal_density_diffrn      2.680
_symmetry_space_group_name_H-M 'R -3 c'
loop_
_space_group_symop_operation_xyz
  'x,y,z'
  '2/3+x,1/3+y,1/3+z'
  '1/3+x,2/3+y,2/3+z'
  'x,x-y,1/2+z'
  '2/3+x,1/3+x-y,5/6+z'
  '1/3+x,2/3+x-y,1/6+z'
  'y,x,1/2-z'
  '2/3+y,1/3+x,5/6-z'
  '1/3+y,2/3+x,1/6-z'
  '-x+y,y,1/2+z'
  '2/3-x+y,1/3+y,5/6+z'
  '1/3-x+y,2/3+y,1/6+z'
  '-x,-x+y,1/2-z'
  '2/3-x,1/3-x+y,5/6-z'
  '1/3-x,2/3-x+y,1/6-z'
  '-y,-x,1/2+z'
  '2/3-y,1/3-x,5/6+z'
  '1/3-y,2/3-x,1/6+z'
  'x-y,-y,1/2-z'
  '2/3+x-y,1/3-y,5/6-z'
  '1/3+x-y,2/3-y,1/6-z'
  'y,-x+y,-z'
  '2/3+y,1/3-x+y,1/3-z'
  '1/3+y,2/3-x+y,2/3-z'
  '-x+y,-x,z'
  '2/3-x+y,1/3-x,1/3+z'
  '1/3-x+y,2/3-x,2/3+z'
  '-x,-y,-z'
  '2/3-x,1/3-y,1/3-z'
  '1/3-x,2/3-y,2/3-z'
  '-y,x-y,z'
  '2/3-y,1/3+x-y,1/3+z'
  '1/3-y,2/3+x-y,2/3+z'
  'x-y,x,-z'
  '2/3+x-y,1/3+x,1/3-z'
  '1/3+x-y,2/3+x,2/3-z'
loop_
_atom_site_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
Th   0.15425   0.82091   0.08333
Si1   0.16840   0.90080  -0.08610
Si2   0.06410   0.80730  -0.06890
Si3   0.15950   0.94990   0.05980
Si4   0.09910   0.72890  -0.09290
Si5   0.06450   0.96630   0.05120
Si6   0.00000   0.00000   0.34150
Na1   0.14860   0.89540   0.24130
Na2   0.02870   0.82370   0.11840
O1   0.19250   0.87130  -0.03900
O2   0.16290   0.90540   0.10740
O3   0.13620   0.75480  -0.01950
O4   0.07690   0.81090   0.02040
O5   0.00820   0.80330  -0.08850
O6   0.05870   0.66667  -0.08333
O7   0.06280   0.75630  -0.10990
O8   0.10860   0.85920  -0.11500
O9   0.16580   0.94650  -0.03460
O10   0.19980   0.93130  -0.16280
O11   0.10330   0.94660   0.07620
O12   0.09600   0.01590  -0.00670
O13   0.00000   0.00000   0.25000
O14   0.04320   0.98220   0.12540
Wat15   0.23230   0.00000   0.25000
Wat16   0.09980   0.94220   0.26680
Wat17   0.00000   0.89100   0.25000
Wat18   0.30720   0.04210   0.34080
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
Th 0.01700 0.01700 0.01400 0.00900 -0.00100 0.00100
Si1 0.01600 0.02000 0.01200 0.00700 0.00100 0.00500
Si2 0.01400 0.01900 0.01700 0.00800 -0.00200 -0.00100
Si3 0.01600 0.01300 0.01700 0.00700 0.00000 0.00200
Si4 0.01700 0.01200 0.01300 0.00600 -0.00100 0.00100
Si5 0.03600 0.03900 0.06000 0.02200 0.00000 -0.00300
Si6 0.03900 0.03900 0.07900 0.02000 0.00000 0.00000
Na1 0.11400 0.07600 0.03000 0.06500 0.00800 0.00300
Na2 0.06000 0.14100 0.05300 0.05900 -0.00400 0.00900
O1 0.02700 0.02800 0.01900 0.01700 0.00700 0.01000
O2 0.04500 0.01600 0.01700 0.01700 -0.00400 0.00000
O3 0.03100 0.02500 0.02300 0.01600 -0.01600 -0.00800
O4 0.01900 0.03800 0.01500 0.01600 -0.00200 -0.00400
O5 0.01800 0.05400 0.01700 0.01900 0.00100 -0.00100
O6 0.02200 0.01100 0.04100 0.00600 0.00600 0.01100
O7 0.02900 0.02100 0.02200 0.01700 -0.00700 -0.00500
O8 0.01700 0.01900 0.02400 0.00300 -0.00400 0.00500
O9 0.03000 0.01700 0.01500 0.01000 -0.00100 0.00100
O10 0.02900 0.04000 0.01800 0.01800 0.01300 0.01700
O11 0.02800 0.06500 0.04600 0.03400 0.00200 0.01000
O12 0.06600 0.04900 0.08900 0.02200 0.00800 0.02300
O14 0.05300 0.08300 0.08400 0.04300 0.01100 -0.00900
Wat15 0.21000 0.21000 0.04000 0.10700 0.01200 0.02300
Wat16 0.21000 0.17000 0.13000 0.09000 -0.02500 0.02900
Wat17 0.37000 0.37000 0.38000 0.18700 -0.00300 -0.00200
Wat18 0.15500 0.08000 0.12100 0.05100 0.05800 -0.00900

X-Ray Powder DiffractionHide

Powder Diffraction Data:

d-spacing	Intensity
14.54 Å	(20)
8.17 Å	(30)
7.27 Å	(100)
5.09 Å	(20)
4.17 Å	(70)
3.239 Å	(30)
2.890 Å	(25)

Geological EnvironmentHide

Paragenetic Mode(s):

Paragenetic Mode	Earliest Age (Ga)
Stage 4b: Highly evolved igneous rocks	>3.0
35 : Ultra-alkali and agpaitic igneous rocks

Type Occurrence of ThornasiteHide

Type Locality:

ⓘ Poudrette quarry (De-Mix quarry; Demix quarry; Uni-Mix quarry; Carrière Mont Saint-Hilaire; MSH), Mont Saint-Hilaire, La Vallée-du-Richelieu RCM, Montérégie, Québec, Canada

General Appearance of Type Material:

Anhedral crystals to 0.7 mm, embedded in patches of brockite.

Place of Conservation of Type Material:

Canadian Museum of Nature, Ottawa, Ontario, Canada, number 50770 (holotype).
Royal Ontario Museum, Toronto, Ontario, Canada, number M42070 (cotype).

Associated Minerals at Type Locality:

Yofortierite

Brockite

Analcime

Synonyms of ThornasiteHide

IMA1985-050

Other Language Names for ThornasiteHide

German:Thornasit

Russian:Торнасит

Spanish:Thornasita

Common AssociatesHide

Associated Minerals Based on Photo Data:

4 photos of Thornasite associated with Villiaumite	NaF
3 photos of Thornasite associated with Natrolite	Na₂Al₂Si₃O₁₀ · 2H₂O
2 photos of Thornasite associated with Aegirine	NaFe³⁺Si₂O₆
2 photos of Thornasite associated with Ellingsenite	Na₅Ca₆Si₁₈O₃₈(OH)₁₃ · 6H₂O
1 photo of Thornasite associated with Tuperssuatsiaite	Fe³⁺Fe³⁺₂(Na◻)◻₂Si₈O₂₀(OH)₂(H₂O)₄ · 2H₂O

Related Minerals - Strunz-mindat Grouping Hide

9.GF.05	Terranovaite	(Na,Ca)₈(Si₆₈Al₁₂)O₁₆₀ · 29H₂O	Orth.
9.GF.10	Gottardiite	Na₃Mg₃Ca₅Al₁₉Si₁₁₇O₂₇₂ · 93H₂O	Orth. mmm (2/m 2/m 2/m) : Cmca
9.GF.15	Lovdarite	K₂Na₆Be₄Si₁₄O₃₆ · 9H₂O	Orth. mm2
9.GF.20	Gaultite	Na₄Zn₂Si₇O₁₈ · 5H₂O	Orth. mm2 : Fdd2
9.GF.25	Chiavennite	CaMnBe₂Si₅O₁₃(OH)₂ · 2H₂O	Mon. 2/m : P2₁/b
9.GF.25	Ferrochiavennite	Ca_1-2Fe[(Si,Al,Be)₅Be₂O₁₃(OH)₂] · 2H₂O	Mon. 2/m : P2₁/b
9.GF.30	Tschernichite	(Ca,Na₂)[Al₂Si₄O₁₂] · 4-8H₂O	Tet. 4/mmm (4/m 2/m 2/m) : P4/mmm
9.GF.35	Mutinaite	Na₃Ca₄Si₈₅Al₁₁O₁₉₂ · 60H₂O	Orth. mmm (2/m 2/m 2/m) : Pnma
9.GF.40	Tschörtnerite	Ca₄(Ca,Sr,K,Ba)₃Cu₃[Al₃Si₃O₁₂]₄(OH)₈ · nH₂O	Iso. m3m (4/m 3 2/m) : Fm3m
9.GF.55	Direnzoite	NaK₆MgCa₂(Al₁₃Si₄₇O₁₂₀) · 36H₂O	Orth. mmm (2/m 2/m 2/m) : Pmmn
9.GF.60	Meierite	Ba₄₄Si₆₆Al₃₀O₁₉₂Cl₂₅(OH)₃₃	Iso. m3m (4/m 3 2/m) : Im3m
9.GF.65	Rongibbsite	Pb₂(Si₄Al)O₁₁(OH)	Mon. 2/m : B2/m

Fluorescence of ThornasiteHide

In UV light:

Bright apple-green under long- and short-wave ultraviolet light.

Other InformationHide

Thermal Behaviour:

Heating at 300°C results in complete collapse of the structure.

Notes:

Slightly metamict.

Slightly attacked by 1:1 HCl at room temperature. Unaffected by either 1:1 HNO3 or H2SO4.

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 ThornasiteHide

mindat.org URL:

https://www.mindat.org/min-3947.html
Please feel free to link to this page.

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External Links:

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Raman and XRD data at RRUFF project

References and PDF downloads at RRUFF project

American Mineralogist Crystal Structure Database

Handbook of Mineralogy page PDF

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References for ThornasiteHide

Reference List:

Ansell, V. E., Chao, George Y. (1987) Thornasite, a new hydrous sodium thorium silicate from Mont St-Hilaire, Quebec. The Canadian Mineralogist, 25. 181-183

Horváth, László, Gault, Robert A., Tarassoff, Peter, Pfenninger-Horváth, Elsa (1998) Mineralogy of the Saint-Amable Sill, Varennes and Saint-Amable, Quebec. The Mineralogical Record, 29 (2) 83-118

Krivovichev, Sergey V., Burns, Peter C., Li, Yaping, Krivovichev, Sergey V., Burns, Peter C. (2000) The crystal structure of thornasite, Na₁₂Th₃[Si₈O₁₉]₄(H₂O)₁₈: A novel interrupted silicate framework. American Mineralogist, 85 (10) 1521-1525 doi:10.2138/am-2000-1025

LI, Y., KRIVOVICHEV, V., BURNS, P.C. (2001) Errata. American Mineralogist, 86, 384.

(2023) Thornasite. Handbook of Mineralogy. Mineralogical Society of America

Localities for ThornasiteHide

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 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.


Canada (TL)
Québec Montérégie La Vallée-du-Richelieu RCM Mont Saint-Hilaire ⓘ Poudrette quarry (De-Mix quarry; Demix quarry; Uni-Mix quarry; Carrière Mont Saint-Hilaire; MSH) (TL)	166-175. +5 other references
Lajemmerais RCM Varennes & St-Amable ⓘ Saint-Amable sill	Horváth et al. (1998)
ⓘ Demix-Varennes quarry	Horváth et al. (1998)

Namibia
Khomas Region Windhoek Rural Aris ⓘ Aris Quarries	Paula Piilonen +3 other references

Thornasite

About ThornasiteHide

Unique IdentifiersHide

IMA Classification of ThornasiteHide

Classification of ThornasiteHide

Mineral SymbolsHide

Physical Properties of ThornasiteHide

Optical Data of ThornasiteHide

Chemistry of ThornasiteHide

Crystallography of ThornasiteHide

Crystal StructureHide

X-Ray Powder DiffractionHide

Geological EnvironmentHide

Type Occurrence of ThornasiteHide

Synonyms of ThornasiteHide

Other Language Names for ThornasiteHide

Common AssociatesHide

Related Minerals - Strunz-mindat GroupingHide

Fluorescence of ThornasiteHide

Other InformationHide

Internet Links for ThornasiteHide

References for ThornasiteHide

Localities for ThornasiteHide

Locality ListHide

Related Minerals - Strunz-mindat Grouping Hide