Umbrianite
A valid IMA mineral species
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About Umbrianite
Flag of Umbria, Italy
Formula:
K7Na2Ca2[Al3Si10O29]F2Cl2
Colour:
colorless
Lustre:
Vitreous
Hardness:
5
Specific Gravity:
2.49 (Calculated)
Crystal System:
Orthorhombic
Name:
The mineral is named for Umbria, the region of central Italy where its type locality, the Pian di Celle volcano, is situated.
Type Locality:
Unique Identifiers
Mindat ID:
42376
Long-form identifier:
mindat:1:1:42376:6
IMA Classification of Umbrianite
Approved
IMA Formula:
K7Na2Ca2[Al3Si10O29]F2Cl2
Approval year:
2011
First published:
2013
Type description reference:
Sharygin, Victor V., Pekov, Igor V., Zubkova, Natalia V., Khomyakov, Alexander P., Stoppa, Francesco, Pushcharovsky, Dmitry Yu. (2013) Umbrianite, K7Na2Ca2[Al3Si10O29]F2Cl2, a new mineral species from melilitolite of the Pian di Celle volcano, Umbria, Italy. European Journal of Mineralogy, 25 (4) 655-669 doi:10.1127/0935-1221/2013/0025-2306
Classification of Umbrianite
9.EB.25
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
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 |
|---|---|---|
| Ubn | 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 Umbrianite
Vitreous
Transparency:
Transparent
Colour:
Colorless
Streak:
White
Hardness:
5 on Mohs scale
Hardness:
VHN20=473 kg/mm2 - Vickers
Cleavage:
Perfect
perfect on (010) and distinct on (100) and (001).
perfect on (010) and distinct on (100) and (001).
Fracture:
Irregular/Uneven, Step-Like
Density:
2.49 g/cm3 (Calculated)
Optical Data of Umbrianite
Type:
Biaxial (-)
RI values:
nα = 1.537(2) nβ = 1.543(2) nγ = 1.544(2)
2V:
Measured: 30° (10), Calculated: 44.3°
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:
None to Very Low
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.
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.
Dispersion:
none
Pleochroism:
Non-pleochroic
Chemistry of Umbrianite
Mindat Formula:
K7Na2Ca2[Al3Si10O29]F2Cl2
Element Weights:
Crystallography of Umbrianite
Crystal System:
Orthorhombic
Class (H-M):
mmm(2/m2/m2/m) - Dipyramidal
Space Group:
Pmmn
Setting:
Pmmn
Cell Parameters:
a = 7.0618(5) Å, b = 38.420(2) Å, c = 6.5734(4) Å
Ratio:
a:b:c = 0.184 : 1 : 0.171
Unit Cell V:
1,783.46 ų (Calculated from Unit Cell)
Z:
2
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
Remove metal-metal sticks
Big Balls | Small Balls | Just Balls | Spacefill
Polyhedra Off | Si Polyhedra | All Polyhedra
Remove metal-metal sticks
Display Options
Black Background | White Background
Perspective On | Perspective Off
2D | Stereo | Red-Blue | Red-Cyan
Black Background | White Background
Perspective On | Perspective Off
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
Console Off | On | Grey | Yellow
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) |
|---|---|---|---|---|---|---|---|
| 0020030 | Umbrianite | Sharygin V V, Pekov I V, Zubkova N V, Khomyakov A P, Stoppa F, Pushcharovsky D Y (2013) Umbrianite, K7Na2Ca2[Al3Si10O29]F2Cl2, a new mineral species from melilitolite of the Pian di Celle volcano, Umbria, Italy European Journal of Mineralogy 25 655-669 | 2013 | Pian di Celle volcano, Umbria, Italy | 0 | 293 |
CIF Raw Data - click here to close
X-Ray Powder Diffraction
Powder Diffraction Data:
| d-spacing | Intensity |
|---|---|
| 9.65 Å | (100) |
| 6.91 Å | (43) |
| 6.59 Å | (97) |
| 3.884 Å | (25) |
| 3.293 Å | (77) |
| 3.118 Å | (70) |
| 2.903 Å | (52) |
| 2.819 Å | (53) |
Reference:
Sharygin, Victor V., Pekov, Igor V., Zubkova, Natalia V., Khomyakov, Alexander P., Stoppa, Francesco, Pushcharovsky, Dmitry Yu. (2013) Umbrianite, K7Na2Ca2[Al3Si10O29]F2Cl2, a new mineral species from melilitolite of the Pian di Celle volcano, Umbria, Italy. European Journal of Mineralogy, 25 (4) 655-669 doi:10.1127/0935-1221/2013/0025-2306
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 Umbrianite
General Appearance of Type Material:
rectangular, lamellar or lath-shaped crystals (up to 25 x 30 x 200 mm in size), typically coarse and flattened on {010}, and their sheaflike clusters (up to 200–500 mm across) in a groundmass of melilitolite
Place of Conservation of Type Material:
Type material is deposited in the collections of the Fersman Mineralogical Museum of the Russian Academy of Sciences, Moscow, Russia, registration number 4157/1.
Geological Setting of Type Material:
Vesicular melilitolites
Associated Minerals at Type Locality:
Reference:
Sharygin, Victor V., Pekov, Igor V., Zubkova, Natalia V., Khomyakov, Alexander P., Stoppa, Francesco, Pushcharovsky, Dmitry Yu. (2013) Umbrianite, K7Na2Ca2[Al3Si10O29]F2Cl2, a new mineral species from melilitolite of the Pian di Celle volcano, Umbria, Italy. European Journal of Mineralogy, 25 (4) 655-669 doi:10.1127/0935-1221/2013/0025-2306
Synonyms of Umbrianite
Other Language Names for Umbrianite
Dutch:Umbrianiet
German:Umbrianit
Common Associates
Associations Based on Photo Data:
| 6 photos of Umbrianite associated with Fluorophlogopite | KMg3(Si3Al)O10F2 |
| 3 photos of Umbrianite associated with Magnetite | Fe2+Fe3+2O4 |
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.15 | Monteregianite-(Y) | (Na,K)6(Y,Ca)2Si16O38 · 10H2O |
| 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.30 | Fivegite | K4Ca2[AlSi7O17(O2-xOHx)][(H2O)2-xOHx]Cl |
Radioactivity
Radioactivity:
| Element | % Content | Activity (Bq/kg) | Radiation Type |
|---|---|---|---|
| Uranium (U) | 0.0000% | 0 | α, β, γ |
| Thorium (Th) | 0.0000% | 0 | α, β, γ |
| Potassium (K) | 20.5085% | 6,358 | β, γ |
For comparison:
- Banana: ~15 Bq per fruit
- Granite: 1,000–3,000 Bq/kg
- EU exemption limit: 10,000 Bq/kg
Note: Risk is shown relative to daily recommended maximum exposure to non-background radiation of 1000 µSv/year. Note that natural background radiation averages around 2400 µSv/year so in reality these risks are probably extremely overstated! With infrequent handling and safe storage natural radioactive minerals do not usually pose much risk.
Interactive Simulator:
Note: The mass selector refers to the mass of radioactive mineral present, not the full specimen, also be aware that the matrix may also be radioactive, possibly more radioactive than this mineral!
Activity: –
| Distance | Dose rate | Risk |
|---|---|---|
| 1 cm | ||
| 10 cm | ||
| 1 m |
The external dose rate (D) from a radioactive mineral is estimated by summing the gamma radiation contributions from its Uranium, Thorium, and Potassium content, disregarding daughter-product which may have a significant effect in some cases (eg 'pitchblende'). This involves multiplying the activity (A, in Bq) of each element by its specific gamma ray constant (Γ), which accounts for its unique gamma emissions. The total unshielded dose at 1 cm is then scaled by the square of the distance (r, in cm) and multiplied by a shielding factor (μshield). This calculation provides a 'worst-case' or 'maximum risk' estimate because it assumes the sample is a point source and entirely neglects any self-shielding where radiation is absorbed within the mineral itself, meaning actual doses will typically be lower. The resulting dose rate (D) is expressed in microsieverts per hour (μSv/h).
D = ((AU × ΓU) + (ATh × ΓTh) + (AK × ΓK)) / r2 × μshield
Fluorescence of Umbrianite
none
Other Information
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 Umbrianite
mindat.org URL:
https://www.mindat.org/min-42376.html
Please feel free to link to this page.
Please feel free to link to this page.
Search Engines:
External Links:
Mineral Dealers:
References for Umbrianite
Reference List:
Williams, P. A., Hatert, F., Pasero, M., Mills, S. J. (2011) New minerals and nomenclature modifications approved in 2011. CNMNC Newsletter No 11. Mineralogical Magazine, 75 (6) 2887-2893 doi:10.1180/minmag.2011.075.6.2887
Sharygin, Victor V., Pekov, Igor V., Zubkova, Natalia V., Khomyakov, Alexander P., Stoppa, Francesco, Pushcharovsky, Dmitry Yu. (2013) Umbrianite, K7Na2Ca2[Al3Si10O29]F2Cl2, a new mineral species from melilitolite of the Pian di Celle volcano, Umbria, Italy. European Journal of Mineralogy, 25 (4) 655-669 doi:10.1127/0935-1221/2013/0025-2306
Localities for Umbrianite
Showing 2 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.
DR Congo | |
| Andersen et al. (2014) |
Italy (TL) | |
| Sharygin et al. (2013) +1 other reference |
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Vispi Quarry, San Venanzo, Terni Province, Umbria, Italy