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Ferrierite-NH4
A valid IMA mineral species
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About Ferrierite-NH4
Walter F. Ferrier
Formula:
(NH4,Mg0.5)5(Al5Si31O72) · 22H2O
Colour:
White
Lustre:
Silky
Specific Gravity:
2.154 (Calculated)
Crystal System:
Orthorhombic
Member of:
Name:
Ammonium dominant member of ferrierite group.
Name Encoding
Formatted:
ferrierite-NH4
HTML:
ferrierite-NH<sub>4</sub>
LaTeX:
ferrierite-NH\$\_4\$
Unique Identifiers
Mindat ID:
52850
Long-form identifier:
mindat:1:1:52850:2
Similar Names
| Ferrierite-Na | A valid IMA mineral species | (Na,K)5(Si31Al5)O72 · 18H2O |
IMA Classification of Ferrierite-NH4
Approved
Approval year:
2018
First published:
2019
Type description reference:
Classification of Ferrierite-NH4
9.GD.50
9 : SILICATES (Germanates)
G : Tektosilicates with zeolitic H2O; zeolite family
D : Chains of 6-membered rings â tabular zeolites
9 : SILICATES (Germanates)
G : Tektosilicates with zeolitic H2O; zeolite family
D : Chains of 6-membered rings â tabular zeolites
Mineral Symbols
As of 2021 there are now IMAâCNMNC approved mineral symbols (abbreviations) for each mineral species, useful for tables and diagrams.
| Symbol | Source | Reference for Standard |
|---|---|---|
| Frr-NH4 | IMAâCNMNC | Warr, L.N. (2021). IMAâCNMNC approved mineral symbols. Mineralogical Magazine, 85(3), 291-320. doi:10.1180/mgm.2021.43 |
Physical Properties of Ferrierite-NH4
Silky
Transparency:
Transparent
Colour:
White
Streak:
White
Cleavage:
None Observed
Density:
2.154 g/cm3 (Calculated)
Optical Data of Ferrierite-NH4
Type:
Biaxial (+)
RI values:
nα = 1.518(2) nβ = 1.520(2) nγ = 1.522(2)
Max. Birefringence:
δ = 0.004
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 ”m 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 ”m 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 (90°) 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 (90°) is estimated from its recorded refractive indices and optic sign, not from a direct 2V measurement.
Optical Extinction:
Z = c.
Pleochroism:
Non-pleochroic
Chemistry of Ferrierite-NH4
Mindat Formula:
(NH4,Mg0.5)5(Al5Si31O72) · 22H2O
Element Weights:
Crystallography of Ferrierite-NH4
Crystal System:
Orthorhombic
Class (H-M):
mmm(2/m2/m2/m) - Dipyramidal
Space Group:
Immm
Setting:
Immm
Cell Parameters:
a = 19.10(1) Å, b = 14.15(1) Å, c = 7.489(3) Å
Ratio:
a:b:c = 1.35 : 1 : 0.529
Unit Cell V:
2,024.01 Ă
Âł (Calculated from Unit Cell)
Z:
1
Morphology:
Very thin flattened prismatic crystals elongated along (001).
X-Ray Powder Diffraction
Powder Diffraction Data:
| d-spacing | Intensity |
|---|---|
| 9.52 Ă | (97) |
| 6.95 Ă | (28) |
| 6.60 Ă | (19) |
| 3.988 Ă | (61) |
| 3.784 Ă | (19) |
| 3.547 Ă | (73) |
| 3.482 Ă | (100) |
| 3.143 Ă | (37) |
Reference:
Comments:
From Type Description.
Geological Environment
Paragenetic Mode(s):
| Paragenetic Mode | Earliest Age (Ga) |
|---|---|
| Stage 10a: Neoproterozoic oxygenation/terrestrial biosphere | <0.6 |
| 49 : Oxic cellular biomineralization (see also #44) | <0.54 |
| 50 : Coal and/or oil shale minerals | <0.36 |
| 53 : Other minerals with taphonomic origins | <0.4 |
Type Occurrence of Ferrierite-NH4
General Appearance of Type Material:
Radiating aggregates up to 2 mm across consisting of thin flattened prismatic crystals.
Place of Conservation of Type Material:
Type material is deposited in the collections of the Fersman Mineralogical Museum, Russian Academy of Sciences, Moscow, Russia, registration number 5120/1.
Geological Setting of Type Material:
Coal deposit.
Associated Minerals at Type Locality:
Reference:
Synonyms of Ferrierite-NH4
Other Language Names for Ferrierite-NH4
Dutch:Ferrieriet-NH4
German:Ferrierit-NH4
Relationship of Ferrierite-NH4 to other Species
Member of:
Other Members of Ferrierite Subgroup:
| Ferrierite-K | (K,Na)5(Si31Al5)O72 · 18H2O | Orth. mmm(2/m2/m2/m) : Immm |
| Ferrierite-Mg | [Mg2(K,Na)2Ca0.5](Si29Al7)O72 · 18H2O | Orth. mmm(2/m2/m2/m) : Pnnm |
| Ferrierite-Na | (Na,K)5(Si31Al5)O72 · 18H2O | Mon. 2/m : P21/c |
Common Associates
Associations Based on Photo Data:
Related Minerals - Strunz-mindat Grouping
| 9.GD.05 | Gmelinite-Ca | Ca2(Si8Al4)O24 · 11H2O |
| 9.GD.05 |
JeniĆĄĆŻv Ăjezd, BĂlina coal mine, BĂlina, Teplice District, ĂstĂ nad Labem Region, Czech Republic