Log In
Neptunite Group
A group of related mineral species
This page is currently not sponsored. Click here to sponsor this page.
About Neptunite Group
The general formula can be given as KNa2(M12M22)M3(Si4O12)2, where the similar octahedrally coordinated M1 and M2 sites are grouped for nomenclature purposes and may contain Fe2+, Mn2+, Mg2+, Ti4+ and V4+.
M1' = Li, Fe2+, M2 = Fe2+, Mn2+, Mg and M3 = Ti, Fe2+, V4+.
M1' = Li, Fe2+, M2 = Fe2+, Mn2+, Mg and M3 = Ti, Fe2+, V4+.
Unique Identifiers
Mindat ID:
39911
Long-form identifier:
mindat:1:1:39911:3
Chemical Analysis
Oxide wt%:
| 1 | 2 | |
|---|---|---|
| SiO2 | 51.53 % | 52.29 % |
| TiO2 | 18.13 % | 17.38 % |
| FeO | 10.91 % | 11.92 % |
| MnO | 4.97 % | 2.27 % |
| MgO | 0.49 % | 1.55 % |
| K2O | 4.88 % | 5.58 % |
| Na2O | 9.26 % | 6.81 % |
| CaO | 0.62 % | |
| Li2O | 1.63 % | |
| Total: | 100.17 % | 100.05 % |
Sample references:
| ID | Type | Locality | Reference | Notes |
|---|---|---|---|---|
| 1 | Type Specimen | Narssârssuk pegmatite, Narsaarsuk Plateau, Igaliku, Kujalleq, Greenland | Wet-chemical analysis (Flink), analysis incomplete, Li not analyzed | |
| 2 | California State Gem Mine, Santa Rita Peak, San Benito County, California, USA | Microprobe |
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) |
|---|---|---|---|---|---|---|---|
| 0015717 | Manganoneptunite | Zolotarev A A, Krivovichev S V, Yakovenchuk V N (2007) Refinement of the mangan-neptunite structure Zapiski Vserossijskogo Mineralogicheskogo Obshchestva 136 118-123 | 2007 | Mt. Kaskasnyuncharr, the Khibiny alkaline pluton, Russia | 0 | 293 | |
| 0013131 | Watatsumiite | Matsubara S, Miyawaki R, Kurosawa M, Suzuki Y (2003) Watatsumiite, KNa2LiMn2V2Si8O24, a new mineral from the Tanohata mine, Iwate Prefecture, Japan Journal of Mineralogical and Petrological Sciences 98 142-150 |  | 2003 | metamorphosed manganese ore deposit, Tanohata mine, Iwate Prefecture, Japan | 0 | 293 |
| 0018847 | Neptunite | Cannillo E, Mazzi F, Rossi G (1966) The crystal structure of neptunite Acta Crystallographica 21 200-208 |  | 1966 | San Benito, California, USA | 0 | 293 |
| 0018809 | Manganoneptunite | Borisov S V, Klevtsova R F, Bakakin V V, Belov N V (1966) The crystal structure of neptunite Soviet Physics Crystallography 10 684-689 | 1966 | Lovozero, Russia | 0 | 293 |
CIF Raw Data - click here to close
Relationship of Neptunite Group to other Species
Neptunite Group Members:
| Magnesioneptunite | KNa2Li(Mg)2Ti2[Si4O12]2 | Mon. 2/m : B2/b |
| Manganoneptunite | KNa2Li(Mn2+)2Ti2[Si4O12]2 | Mon. m : Bb |
| Neptunite | KNa2Li(Fe2+)2Ti2[Si4O12]2 | Mon. m : Bb |
| Rotherkopfite | KNa2Fe2+(Fe2+)2(Ti1.5Fe2+0.5)[Si4O12]2 | Mon. 2/m : B2/b |
| Watatsumiite | KNa2Li(Mn2+)2V4+2[Si4O12]2 | Mon. m : Bb |
Click on any node to view relationships. Formula-derived relationship network for the group members above. Use Find related species to add formula-neighbour species outside the current group view. Solid links show inferred chemical differences; dashed violet links show same-formula crystallographic differences. Hydration states are not treated as relationship changes. These relationships do not imply any real-world substitution reactions between these species.
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 Neptunite Group
mindat.org URL:
https://www.mindat.org/min-39911.html
Please feel free to link to this page.
Please feel free to link to this page.
Search Engines:
Mineral Dealers:
References for Neptunite Group
Reference List:
Kampf, A. R., Möhn, G., Ma, C., Rossman, G. R., Désor, J., Guan, Y. (2024) Rotherkopfite, KNa₂(Fe²⁺2.5Ti⁴⁺1.5)Fe²⁺(Si₄O₁₂)₂, a new neptunite-group mineral without essential lithium, from Rother Kopf, Eifel volcanic fields, Germany. European Journal of Mineralogy, 36 (4). 605-614 doi:10.5194/ejm-36-605-2024
Localities for Neptunite Group
Showing 109 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.
California State Gem Mine, Santa Rita Peak, San Benito County, California, USA