Monteregianite-(Y)
A valid IMA mineral species
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About Monteregianite-(Y)
View of the Poudrette quarry, 2005 September
Poudrette quarry, Mont Saint-Hilaire, La Vallée-du-Richelieu RCM, Montérégie, Québec, Canada
Poudrette quarry, Mont Saint-Hilaire, La Vallée-du-Richelieu RCM, Montérégie, Québec, Canada
Formula:
(Na,K)6(Y,Ca)2Si16O38 · 10H2O
Colour:
Colorless, white, grey, rarely mauve or pale green
Lustre:
Vitreous, Silky
Hardness:
3½
Specific Gravity:
2.42
Crystal System:
Monoclinic
Member of:
Name:
Originally named monteregianite by George Y. Chao in 1978 after the Monteregian Hills, a series of monadnocks or prominent hills on an otherwise flat landscape in eastern Quebec, Canada. The type locality for the mineral, Poudrette Quarry, Mont Saint-Hilaire, is on one of these hills. The suffix/modifier follows the Levinson rule, indicating that the predominant essential REE is yttrium. It was added by the IMA in 1987.
Before being described, the mineral was referred to as UK-6 in Mont Saint-Hilaire related literature.
Before being described, the mineral was referred to as UK-6 in Mont Saint-Hilaire related literature.
Unique Identifiers
Mindat ID:
2765
Long-form identifier:
mindat:1:1:2765:2
Similar Names
| Monteregianite-(Y)-Wickenburgite Series | A solid-solution series between two end-member minerals |
IMA Classification of Monteregianite-(Y)
Approved
IMA status notes:
Renamed by the IMA
IMA Formula:
KNa2YSi8O19·5H2O
Approval year:
1972
First published:
1978
Classification of Monteregianite-(Y)
9.EB.15
9 : SILICATES (Germanates)
E : Phyllosilicates
B : Double nets with 4- and 6-membered rings
9 : SILICATES (Germanates)
E : Phyllosilicates
B : Double nets with 4- and 6-membered rings
72.5.1.2
72 : PHYLLOSILICATES Two-Dimensional Infinite Sheets with Other Than Six-Membered Rings
5 : Two-Dimensional Infinite Sheets with Other Than Six-Membered Rings with corrugated and complex layers
72 : PHYLLOSILICATES Two-Dimensional Infinite Sheets with Other Than Six-Membered Rings
5 : Two-Dimensional Infinite Sheets with Other Than Six-Membered Rings with corrugated and complex layers
14.8.7
14 : Silicates not Containing Aluminum
8 : Silicates of Group III metals other than Al
14 : Silicates not Containing Aluminum
8 : Silicates of Group III metals other than Al
Mineral Symbols
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 |
|---|---|---|
| Mreg-Y | 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 Monteregianite-(Y)
Vitreous, Silky
Transparency:
Transparent, Translucent, Opaque
Colour:
Colorless, white, grey, rarely mauve or pale green
Streak:
White
Hardness:
3½ on Mohs scale
Cleavage:
Perfect
{010} perfect, {001} very good,{100} fair.
{010} perfect, {001} very good,{100} fair.
Density:
2.42 g/cm3 (Measured) 2.391 g/cm3 (Calculated)
Optical Data of Monteregianite-(Y)
Type:
Biaxial (+)
RI values:
nα = 1.51 nβ = 1.513 nγ = 1.517
Max. Birefringence:
δ = 0.007
Based on recorded range of RI values above.
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.
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.
Surface Relief:
Low (negative)
Relative to Canada balsam mounting medium (n ≈ 1.537).
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.
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.
No measured or calculated 2V is on file for this mineral, so the value used here (82°) is estimated from its recorded refractive indices and optic sign, not from a direct 2V measurement.
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.
No measured or calculated 2V is on file for this mineral, so the value used here (82°) is estimated from its recorded refractive indices and optic sign, not from a direct 2V measurement.
Dispersion:
none
Optical Extinction:
X = c; Y = a; Z = b.
Chemistry of Monteregianite-(Y)
Mindat Formula:
(Na,K)6(Y,Ca)2Si16O38 · 10H2O
Element Weights:
Crystallography of Monteregianite-(Y)
Crystal System:
Monoclinic
Class (H-M):
2/m - Prismatic
Cell Parameters:
a = 9.512(2) Å, b = 23.956(4) Å, c = 9.617(2) Å
β = 93.85(1)°
β = 93.85(1)°
Ratio:
a:b:c = 0.397 : 1 : 0.401
Unit Cell V:
2,186.48 ų (Calculated from Unit Cell)
Z:
2
Morphology:
Bounded by {010}, {001} and {100}. Some also show {101}.
Comment:
Space group P21/n.
Crystal Structure
Load
Unit Cell | Unit Cell Packed
2x2x2 | 3x3x3 | 4x4x4
Unit Cell | Unit Cell Packed
2x2x2 | 3x3x3 | 4x4x4
Show
Big Balls | Small Balls | Just Balls | Spacefill
Polyhedra Off | Si Polyhedra | All Polyhedra
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Big Balls | Small Balls | Just Balls | Spacefill
Polyhedra Off | Si Polyhedra | All Polyhedra
Remove metal-metal sticks
Display Options
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Perspective On | Perspective Off
2D | Stereo | Red-Blue | Red-Cyan
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2D | Stereo | Red-Blue | Red-Cyan
View
CIF File Best | x | y | z | a | b | c
CIF File Best | x | y | z | a | b | c
Rotation
Stop | Start
Stop | Start
Labels
Console Off | On | Grey | Yellow
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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) |
|---|---|---|---|---|---|---|---|
| 0001072 | Monteregianite-(Y) | Ghose S, Sen Gupta P K, Campana C F (1987) Symmetry and crystal structure of monteregianite, Na4K2Y2Si16O38.10H2O, a double-sheet silicate with zeolitic properties no longer have the original data, so they cannot check American Mineralogist 72 365-374 |  | 1987 | 0 | 293 |
CIF Raw Data - click here to close
X-Ray Powder Diffraction
Powder Diffraction Data:
| d-spacing | Intensity |
|---|---|
| 12.00 Å | (100) |
| 7.03 Å | (100) |
| 6.55 Å | (40) |
| 6.02 Å | (50) |
| 4.42 Å | (100) |
| 3.405 Å | (50) |
| 3.026 Å | (50) |
| 2.873 Å | (80) |
Geological Environment
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 Monteregianite-(Y)
General Appearance of Type Material:
Needle-shaped crystals in radiating clusters and as groups of tabular crystals.
Place of Conservation of Type Material:
Canadian Museum of Nature, Ottawa, Canada, 37130.
National Museum of Natural History, Washington, D.C., USA, 145548.
National Museum of Natural History, Washington, D.C., USA, 145548.
Geological Setting of Type Material:
Miarolitic cavities and thermally metamorphosed inclusions and rheomorphic breccias in nepheline syenite.
Associated Minerals at Type Locality:
Synonyms of Monteregianite-(Y)
Other Language Names for Monteregianite-(Y)
Relationship of Monteregianite-(Y) to other Species
Member of:
Other Members of Rhodesite Group:
| Delhayelite | (Na,K)10Ca5Al6Si32O80(Cl2,F2,SO4)3 · 18H2O | Orth. |
| Fivegite | K4Ca2[AlSi7O17(O2-xOHx)][(H2O)2-xOHx]Cl | Orth. mm2 : Pmn21 |
| Hydrodelhayelite | KCa2AlSi7O17(OH)2 · 6H2O | Orth. mm2 |
| Melansonite | Na◻KZrSi8O19 · 5H2O | Orth. mmm(2/m2/m2/m) : Pmma |
| Natromelansonite | Na3Zr[Si7AlO19] · 4H2O | Mon. 2/m : P21/m |
| Rhodesite | KHCa2Si8O19 · 5H2O | Orth. mmm(2/m2/m2/m) |
Forms a series with:
Common Associates
Associations Based on Photo Data:
| 32 photos of Monteregianite-(Y) associated with Calcite | CaCO3 |
| 15 photos of Monteregianite-(Y) associated with Albite | Na(AlSi3O8) |
| 13 photos of Monteregianite-(Y) associated with Quartz | SiO2 |
| 11 photos of Monteregianite-(Y) associated with Leucosphenite | BaNa4Ti2B2Si10O30 |
| 10 photos of Monteregianite-(Y) associated with Pectolite | NaCa2Si3O8(OH) |
| 7 photos of Monteregianite-(Y) associated with Fluorite | CaF2 |
| 4 photos of Monteregianite-(Y) associated with Fluorapatite | Ca5(PO4)3F |
| 4 photos of Monteregianite-(Y) associated with Arfvedsonite Root Name Group | ANa2(C2+4Fe3+}Si8O22W2 |
| 3 photos of Monteregianite-(Y) associated with Vinogradovite | Na4Ti4(Si2O6)2[(Si,Al)4O10]O4 · (H2O,Na,K)3 |
| 2 photos of Monteregianite-(Y) associated with Chabazite-Na | (Na2,K2,Ca,Sr,Mg)2[Al2Si4O12]2 · 12H2O |
Related Minerals - Strunz-mindat Grouping
| 9.EB. | Natromelansonite | Na3Zr[Si7AlO19] · 4H2O |
| 9.EB.05 | Melansonite | Na◻KZrSi8O19 · 5H2O |
| 9.EB.05 | Rhodesite | KHCa2Si8O19 · 5H2O |
| 9.EB.05 | Macdonaldite | BaCa4Si16O36(OH)2 · 10H2O |
| 9.EB.10 | Hydrodelhayelite | KCa2AlSi7O17(OH)2 · 6H2O |
| 9.EB.10 | Delhayelite | (Na,K)10Ca5Al6Si32O80(Cl2,F2,SO4)3 · 18H2O |
| 9.EB.20 | Carletonite | KNa4Ca4Si8O18(CO3)4(OH,F) · H2O |
| 9.EB.20 | Fluorcarletonite | KNa4Ca4Si8O18(CO3)4F · H2O |
| 9.EB.25 | Günterblassite | (K,Ca,Ba)2(Fe,Ca,Mg,Na)[(Si,Al)13O25(OH)4] · 7H2O · |
| 9.EB.25 | Hillesheimite | (K,Ca,Ba,◻)2(Mg,Fe,Ca,◻)2[(Si,Al )13O23(OH)6](OH) · 8H2O |
| 9.EB.25 | Umbrianite | K7Na2Ca2[Al3Si10O29]F2Cl2 |
| 9.EB.30 | Fivegite | K4Ca2[AlSi7O17(O2-xOHx)][(H2O)2-xOHx]Cl |
Fluorescence of Monteregianite-(Y)
Fluoresces green under SW UV.
Other Information
IR Spectrum:
Infrared spectra confirm the presence of H2O in the mineral.
Thermal Behaviour:
Three distinct stages of dehydration at 25-80, 80-200, and 200-400 °C.
Notes:
Readily etched by 1:l HCl, HNO3, and 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 Monteregianite-(Y)
mindat.org URL:
https://www.mindat.org/min-2765.html
Please feel free to link to this page.
Please feel free to link to this page.
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References for Monteregianite-(Y)
Reference List:
Chao, George Y. (1978) Monteregianite, a new hydrous sodium potassium yttrium silicate mineral from Mont St-Hilaire, Québec. The Canadian Mineralogist, 16 (4) 561-565
Fleischer, M.; Mandarino, J.A.; Pabst, A. (1980) New mineral names. American Mineralogist, 65 (1-2). 205-210
Ghose, Subrata, Gupta, P. K Sen, Campana, Charles F. (1987) Symmetry and crystal structure of montregianite [sic], Na4F2Y2Si16O38·10H2O, a double-sheet silicate with zeolitic properties. American Mineralogist, 72 (3-4). 365-374
Localities for Monteregianite-(Y)
Showing 1 localities.
symbol to view information about a locality.
The Locality List
- 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).
All localities listed without proper references should be considered as questionable.
Canada (TL) | |
| Chao (1978) +2 other references |
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Poudrette quarry, Mont Saint-Hilaire, La Vallée-du-Richelieu RCM, Montérégie, Québec, Canada