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Riversideite

A valid IMA mineral species - questionable
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02671660017271926183171.jpg
Riversideite

Crestmore, Jurupa Valley, Riverside County, California, USA
07160820017271926207844.jpg
Riversideite

Crestmore quarries, Crestmore, Jurupa Valley, Riverside County, California, USA
08272820017271926231782.jpg
Riversideite

Crestmore quarries, Crestmore, Jurupa Valley, Riverside County, California, USA
02671660017271926183171.jpg
Riversideite

Crestmore, Jurupa Valley, Riverside County, California, USA
07160820017271926207844.jpg
Riversideite

Crestmore quarries, Crestmore, Jurupa Valley, Riverside County, California, USA
08272820017271926231782.jpg
Riversideite

Crestmore quarries, Crestmore, Jurupa Valley, Riverside County, California, USA
02671660017271926183171.jpg
Riversideite

Crestmore, Jurupa Valley, Riverside County, California, USA
07160820017271926207844.jpg
Riversideite

Crestmore quarries, Crestmore, Jurupa Valley, Riverside County, California, USA
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About RiversideiteHide

Formula:
Ca5Si6O16(OH)2 · 2H2O
Alternative: Ca^5(HSi^3O^9)^2.2H^2O
Colour:
White
Lustre:
Silky
Hardness:
3
Specific Gravity:
2.65 (Calculated)
Crystal System:
Orthorhombic
Name:
Named after its discovery locality.
A natural occurrence of riversideite is not yet demonstrated unequivocally and its status should be considered as “questionable” (Biagioni et al., 2015).

The exact structure of riversideite is not known, but a reliable model can be derived from the structures of Tobermorite and Clinotobermorite. In this model, the riversideite structure contains composite layers, consisting of infinite sheets of (CaO7) polyhedra, to both sides of which dreier single chains of (SiO4) tetrahedra are attached, running along the b axis. Those layers are stacked along the c axis and linked by additional calcium ions and water molecules which occupy cavities between the layers (Ferraris et al., 2004).

A very similar structure is found in plombièrite.

Previously known as Tobermorite-9 Å.


Unique IdentifiersHide

Mindat ID:
3427
Long-form identifier:
mindat:1:1:3427:8

IMA Classification of RiversideiteHide

Classification of RiversideiteHide

Strunz-mindat (2026):
9.DG.10

9 : SILICATES (Germanates)
D : Inosilicates
G : Inosilicates with 3-periodic single and multiple chains
Dana 8th ed.:
72.3.2.4

72 : PHYLLOSILICATES Two-Dimensional Infinite Sheets with Other Than Six-Membered Rings
3 : Two-Dimensional Infinite Sheets with Other Than Six-Membered Rings with 3-, 4-, or 5-membered rings and 8-membered rings
Hey's CIM Ref.:
14.5.19

14 : Silicates not Containing Aluminum
5 : Silicates of Ca

Mineral SymbolsHide

As of 2021 there are now IMA–CNMNC approved mineral symbols (abbreviations) for each mineral species, useful for tables and diagrams.

SymbolSourceReference for Standard
RsdIMA–CNMNCWarr, L.N. (2021). IMA–CNMNC approved mineral symbols. Mineralogical Magazine, 85(3), 291-320. doi:10.1180/mgm.2021.43

Physical Properties of RiversideiteHide

Lustre:
Silky
Transparency:
Translucent, Opaque
Colour:
White
Hardness:
3 on Mohs scale
Cleavage:
Perfect
{001}, perfect; {100}, secondary
Density:
2.65(5) g/cm3 (Calculated)

Optical Data of RiversideiteHide

Type:
Biaxial (+)
RI values:
nα = 1.600(2) nβ = 1.601(2) nγ = 1.605(2)
Max. Birefringence:
δ = 0.005
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.

Surface Relief:
Moderate
Dispersion:
r < v weak
Comments:
2V(meas.) = Small.

Chemistry of RiversideiteHide

Mindat Formula:
Ca5Si6O16(OH)2 · 2H2O

Alternative: Ca^5(HSi^3O^9)^2.2H^2O
Element Weights:
Element% weight
O46.046 %
Ca28.836 %
Si24.249 %
H0.870 %

Calculated from ideal end-member formula.
Elements listed:
Ca, H, O, Si - search for minerals with similar chemistry
Common Impurities:
Ti,Al,Fe,Mg

Crystallography of RiversideiteHide

Crystal System:
Orthorhombic
Cell Parameters:
a = 11.3 Å, b = 7.30 Å, c = 18.79 Å
Ratio:
a:b:c = 1.548 : 1 : 2.574
Unit Cell V:
1,549.99 ų (Calculated from Unit Cell)
Z:
4
Comment:
Point Group: n.d.; Space Group: n.d.

X-Ray Powder DiffractionHide

Powder Diffraction Data:
d-spacingIntensity
3.03 Å(vs)
2.33 Å(s)
1.83 Å(s)
9.3 Å(m)
3.59 Å(m)
2.78 Å(m)
1.66 Å(m)
Comments:
from 9.3 ºA product of dehydrated tobermorite.

Geological EnvironmentHide

Paragenetic Mode(s):
Paragenetic ModeEarliest Age (Ga)
High-? alteration and/or metamorphism
31 : Thermally altered carbonate, phosphate, and iron formations
Stage 10a: Neoproterozoic oxygenation/terrestrial biosphere<0.6
51 : Pyrometamorphic minerals (see also #54 and #56)<0.36

Type Occurrence of RiversideiteHide

Synonyms of RiversideiteHide

Other Language Names for RiversideiteHide

Relationship of Riversideite to other SpeciesHide

Member of:
Tobermorite Supergroup
Other Members of Tobermorite Supergroup:
ClinotobermoriteCa5Si6O17 · 5H2OMon.
ParatobermoriteCa5AlSi5O16(OH) · 5H2OMon. 2/m
PlombièriteCa5Si6O16(OH)2 · 7H2OOrth.
Tobermorite GroupCa4+x(AlySi6-y)O15+2x-y · 5H2O

Common AssociatesHide

Associations Based on Photo Data:
8 photos of Riversideite associated with CalciteCaCO3
8 photos of Riversideite associated with TobermoriteCa5Si6O17 · 5H2O
6 photos of Riversideite associated with VesuvianiteCa19Fe3+Al4(Al6Mg2)(◻4)◻[Si2O7]4[(SiO4)10]O(OH)9
4 photos of Riversideite associated with DatoliteCaB(SiO4)(OH)
4 photos of Riversideite associated with 'Ellestadite'
1 photo of Riversideite associated with HarkeriteCa48Mg16[AlSi4O15(OH)]4(BO3)16(CO3)16 · 2(H2O,HCl)

Related Minerals - Strunz-mindat GroupingHide

9.DG.Barrydawsonite-(Y)Na1.5Y0.5CaSi3O8(OH)Mon. 2/m : P21/b
9.DG.ParatobermoriteCa5AlSi5O16(OH) · 5H2OMon. 2/m
9.DG.CalcinaksiteKNaCa(Si4O10) · H2OTric. 1 : P1
9.DG.AlvesiteNaKZrSi6O15 · 2H2OOrth. mmm (2/m 2/m 2/m)
9.DG.02SteedeiteNaMn2[Si3BO9](OH)2Tric. 1 : P1
9.DG.02NolzeiteNaMn2[Si3BO9](OH)2 · 2H2OTric. 1 : P1
9.DG.05MurakamiiteLiCa2Si3O8(OH)Tric. 1 : P1
9.DG.05SeranditeNaMn2+2Si3O8(OH)Tric. 1 : P1
9.DG.05BustamiteCaMn2+(Si2O6)Tric. 1 : P1
9.DG.05PectoliteNaCa2Si3O8(OH)Tric. 1 : P1
9.DG.05TanohataiteLiMn2Si3O8(OH)Tric. 1 : P1
9.DG.05DalnegorskiteCa5Mn(Si3O9)2Tric. 1 : P1
9.DG.05'Wollastonite-1A'CaSiO3Tric. 1 : P1
9.DG.05WollastoniteCa3(Si3O9)Tric. 1 : P1
9.DG.05FerrobustamiteCaFe2+(Si2O6)Tric. 1
9.DG.05SchizoliteNaCaMnSi3O8(OH)Tric. 1 : P1
9.DG.07CascanditeCaScSi3O8(OH)Tric. 1
9.DG.08PlombièriteCa5Si6O16(OH)2 · 7H2OOrth.
9.DG.10ClinotobermoriteCa5Si6O17 · 5H2OMon.
9.DG.10TobermoriteCa5Si6O17 · 5H2OMon. 2 : P21
9.DG.12JusiteNa2Ca15Al4Si16O54 · 17H2O
9.DG.12KenotobermoriteCa4Si6O15(OH)2 · 5H2OMon.
9.DG.15FoshagiteCa4(Si3O9)(OH)2Tric. 1 : P1
9.DG.20JenniteCa9(Si3O9)2(OH)8 · 8H2OTric. 1 : P1
9.DG.20KameneviteK2TiSi3O9 · H2OOrth. 2 2 2 : P21 21 21
9.DG.25ParaumbiteK3Zr2H(Si3O9)2 · nH2OOrth. mm2
9.DG.25UmbiteK2(Zr,Ti)Si3O9 · H2OOrth. 2 2 2 : P21 21 21
9.DG.30SørenseniteNa4SnBe2Si6O16(OH)4Mon. 2/m : B2/b
9.DG.32Escheite Ca2NaMnTi5[Si12O34]O2(OH)3 · 12H2OOrth. mm2 : Ama2
9.DG.35XonotliteCa6(Si6O17)(OH)2Mon. 2/m : B2/m
9.DG.40HillebranditeCa2(SiO3)(OH)2Orth. mmm (2/m 2/m 2/m) : Cmcm
9.DG.45ZoriteNa8(Ti,Nb)5(Si6O17)2(OH,O)5 · 14H2OOrth.
9.DG.45ChivruaiiteCa4(Ti,Nb)5(Si6O17)2(OH,O)5 · 13-14H2OOrth. mmm (2/m 2/m 2/m) : Cmmm
9.DG.50Haineaultite(Na,Ca)5Ca(Ti,Nb)5(Si6O17)2(OH,F)8 · 5H2OOrth. 2 2 2 : C2 2 2
9.DG.55EpididymiteNa2Be2Si6O15 · H2OOrth. mmm (2/m 2/m 2/m) : Pnma
9.DG.60EudidymiteNa2Be2Si6O15 · H2OMon. 2/m : B2/b
9.DG.65ElpiditeNa2ZrSi6O15 · 3H2OOrth.
9.DG.65PatyniteNaKCa4[Si9O23]Tric. 1 : P1
9.DG.67WhelaniteCu2+2Ca6[Si6O17(OH)](CO3)(OH)3 · 2H2OOrth. mm2 : Pnn2
9.DG.70EnricofrancoiteKNaCaSi4O10Tric. 1 : P1
9.DG.70YusupoviteNa2Zr(Si6O15) · 2.5H2OMon. 2/m : B2/m
9.DG.70LitidioniteKNaCuSi4O10Tric. 1 : P1
9.DG.70Fenaksite(K,Na)4(Fe,Mn)2(Si4O10)2(OH,F)Tric. 1 : P1
9.DG.70ManaksiteKNaMnSi4O10Tric. 1 : P1
9.DG.75SenkevichiteCsKNaCa2TiO[Si7O18](OH)Tric. 1 : P1
9.DG.75TinaksiteK2Na(Ca,Mn2+)2TiO[Si7O18(OH)]Tric.
9.DG.75TokkoiteK2Ca4[Si7O18(OH)](OH,F)Tric.
9.DG.80FluorcanasiteK3Na3Ca5Si12O30F4 · H2OMon. m : Bm
9.DG.80CanasiteK3Na3Ca5Si12O30(OH)4Mon. m : Bm
9.DG.85MiseriteK1.5-x(Ca,Y,REE)5(Si6O15)(Si2O7)(OH,F)2 · yH2OTric.
9.DG.90FrankameniteK3Na3Ca5(Si12O30)(F,OH)4 · H2OTric. 1 : P1
9.DG.92Charoite(K,Sr)15-16(Ca,Na)32[Si6O11(O,OH)6]2[Si12O18(O,OH)12]2[Si17O25(O,OH)18]2(OH,F)4 · ~3H2OMon. 2/m : P21/m
9.DG.95YuksporiteK4(Ca,Na)14(Sr,Ba)2(◻,Mn,Fe)(Ti,Nb)4(O,OH)4(Si6O17)2(Si2O7)3(H2O,OH)3Mon. 2/m : P21/m
9.DG.97Eveslogite(Na,K,Ca,Sr,Ba)48 [(Ti,Nb,Mn,Fe2+)12Si48O144(OH)12](F,OH,Cl)14Mon. 2/m : P2/m

Other InformationHide

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 RiversideiteHide

References for RiversideiteHide

Localities for RiversideiteHide

Showing 7 localities.

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.
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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.
Austria
 
  • Styria
    • Südoststeiermark District
      • Klöch
Postl et al. (2012)
Germany
 
  • Bavaria
    • Lower Franconia
      • Haßberge District
        • Maroldsweisach
Wittern (2001)
  • Lower Saxony
    • Osnabrück District
      • Georgsmarienhütte
Schnorrer et al. (2001)
Middle East
 
Gross (1977)
Romania
 
  • Hunedoara County
    • Vaţa de Jos
      • Cerboia Valley
Marincea +2 other references
USA (TL)
 
  • California
    • Riverside County
      • Jurupa Valley
        • Crestmore
[Bull.Dept.Geol.Univ. California (1917)
            • Sky Blue Hill
Woodford et al. (1941) +4 other references
Quick NavTopAbout RiversideiteUnique IdentifiersIMA Classification Classification Mineral SymbolsPhysical Properties Optical Data Chemistry Crystallography X-Ray Powder DiffractionGeological EnvironmentType Occurrence SynonymsOther LanguagesRelationshipsCommon AssociatesStrunz-MindatOther InformationInternet Links References Localities Locality List
 
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