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Loomisite

A valid IMA mineral species
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About LoomisiteHide

02170800017272473434684.jpg
Tom Loomis
Formula:
Ba[Be2P2O8] · H2O
Colour:
White
Lustre:
Vitreous, Silky
Hardness:
3½ - 4
Specific Gravity:
3.46
Crystal System:
Monoclinic
Member of:
Name:
Named after Tom Loomis, mineral collector and dealer from South Dakota, USA, who collected the type material.
Chemically related to minjiangite that may be treated as its anhydrous counterpart. Both are beryllophosphates.

Loomisite is the first natural example with the zeolite ABW-type framework, which is adopted by over 100 synthetic compounds with different chemical compositions.


Unique IdentifiersHide

Mindat ID:
56033
Long-form identifier:
mindat:1:1:56033:1

Similar NamesHide

IMA Classification of LoomisiteHide

Classification of LoomisiteHide

8.DN.

8 : PHOSPHATES, ARSENATES, VANADATES
D : Phosphates, etc. with additional anions, with H2O
N : With only large cations

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

Physical Properties of LoomisiteHide

Vitreous, Silky
Transparency:
Transparent
Colour:
White
Streak:
White
Hardness:
3½ - 4 on Mohs scale
Tenacity:
Brittle
Cleavage:
Perfect
{100} and {110}.
Parting:
None
Density:
3.46(5) g/cm3 (Measured)    3.512 g/cm3 (Calculated)

Optical Data of LoomisiteHide

Type:
Biaxial (+)
RI values:
nα = 1.579(5) nβ = 1.591(5) nγ = 1.606(5)
2V:
Measured: 82° (2), Calculated: 85°
Max. Birefringence:
δ = 0.027
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.

Surface Relief:
Moderate
Dispersion:
very weak with r > v
Pleochroism:
Non-pleochroic

Chemistry of LoomisiteHide

Mindat Formula:
Ba[Be2P2O8] · H2O
Element Weights:
Element% weight
O39.634 %
Ba37.799 %
P17.051 %
Be4.961 %
H0.555 %

Calculated from ideal end-member formula.

Crystallography of LoomisiteHide

Crystal System:
Monoclinic
Class (H-M):
m - Domatic
Cell Parameters:
a = 7.629(2) Å, b = 9.429(2) Å, c = 4.762(1) Å
β = 91.272(5)°
Ratio:
a:b:c = 0.809 : 1 : 0.505
Unit Cell V:
342.46 ų (Calculated from Unit Cell)
Z:
2
Morphology:
Divergent sprays of very thin bladed crystals with a tapered termination.
Twinning:
Pervasively twinned on (100) with the twin law [1 0 0 / 0 -1 0 / 0 0 -1] or consist of multi-crystal intergrowth.
Comment:
Space group Pn

X-Ray Powder DiffractionHide

Type Occurrence of LoomisiteHide

General Appearance of Type Material:
Divergent sprays of very thin bladed crystals that gently taper to a blunt termination. Individual crystals are found up to 0.80 x 0.06 x 0.03 mm.
Place of Conservation of Type Material:
Type material is deposited in the collections of the University of Arizona Alfie Norville Gem and Mineral Museum, 15 N Church Ave, Tucson, AZ 85701, USA, catalogue no. 22710 (holotype), and the RRUFF Project, deposition no. R210017 (cotype).
Geological Setting of Type Material:
Granite pegmatite.
Associated Minerals at Type Locality:

Synonyms of LoomisiteHide

Other Language Names for LoomisiteHide

Dutch:Loomisiet
German:Loomisit

Relationship of Loomisite to other SpeciesHide

Member of:
Other Members of Zeolite Group:
AlflarseniteNaCa2Be3Si4O13(OH) · 2H2OMon. 2 : P21
AmiciteK2Na2Al4Si4O16 · 5H2OMon. 2
Ammonioleucite(NH4)(AlSi2O6)Tet. 4/m : I41/a
AnalcimeNa(AlSi2O6) · H2OTric. 1 : P1
ArzamastseviteK6Al5Si6O20(OH)4ClTet. 42m : I42m
Bellbergite(K,Ba,Sr)2Sr2Ca2(Ca,Na)4[Al3Si3O12]6 · 30H2OHex.
BikitaiteLiAlSi2O6 · H2OTric. 1 : P1
BoggsiteCa8Na3(Si,Al)96O192 · 70H2OOrth. mmm(2/m2/m2/m) : Imma
Brewsterite SubgroupZeolite Group.
Chabazite-Levyne SubgroupM[Al2Si4O12] · 6H2O
ChiavenniteCaMnBe2Si5O13(OH)2 · 2H2OMon. 2/m : P21/b
Clinoptilolite Subgroup(Na/Ca/K)3-6[Al6-7Si29-30O72] · 20H2O
CowlesiteCaAl2Si3O10 · 6H2OOrth. mmm(2/m2/m2/m)
Dachiardite SubgroupZeolite Group.
DirenzoiteNaK6MgCa2(Al13Si47O120) · 36H2OOrth. mmm(2/m2/m2/m) : Pmmn
EdingtoniteBa[Al2Si3O10] · 4H2OOrth. 222 : P212121
EpistilbiteCaAl2Si6O16 · 5H2OMon.
Erionite SubgroupM2[Al4Si14O36] · 15H2O
FabrièsiteNa3Al3Si3O12 · 2H2OOrth. mm2 : Pmm2
Faujasite SubgroupM3.5[Al7Si17O48] · 32H2O
Ferrierite SubgroupName used for unanalysed specimens that could be either ferrierite-K, ferrierite-Mg, ...
FerrochiavenniteCa1-2Fe[(Si,Al,Be)5Be2O13(OH)2] · 2H2OMon. 2/m : P21/b
Flörkeite(K3Ca2Na)[Al8Si8O32] · 12H2OTric. 1 : P1
Garronite Subgroup
GaultiteNa4Zn2Si7O18 · 5H2OOrth. mm2 : Fdd2
Gismondine SubgroupZeolite Group.
Gmelinite SubgroupIn 1997, gmelinite was split into Gmelinite-Ca, Gmelinite-Na and Gmelinite-K.
GobbinsiteNa5(Si11Al5)O32 · 11H2OOrth. mmm(2/m2/m2/m) : Pnma
GoosecreekiteCa[Al2Si6O16] · 5H2OMon. 2 : P21
GottardiiteNa3Mg3Ca5Al19Si117O272 · 93H2OOrth. mmm(2/m2/m2/m) : Cmca
Heulandite Subgroup(Na/Ca/K)5-6[Al8-9 Si27-28 O72] · nH2O
HsianghualiteCa3Li2(Be3Si3O12)F2Iso. 23 : I213
KalborsiteK6Al4BSi6O20(OH)4ClTet. 42m : P421c
KirchhoffiteCs(BSi2O6)Tet. 4/mmm(4/m2/m2/m) : I41/acd
LaumontiteCaAl2Si4O12 · 4H2OMon. 2/m : B2/m
LeuciteK(AlSi2O6)Tet. 4/m : I41/a
LimousiniteBaCa[Be4P4O16] · 6H2OMon. 2/m : P21/b
LithositeK6Al4Si8O25 · 2H2OMon.
LovdariteK2Na6Be4Si14O36 · 9H2OOrth. mm2
MaricopaitePb7Ca2(Si,Al)48O100 · 32H2OOrth.
MartinandresiteBa2(Al4Si12O32) · 10H2OOrth. mmm(2/m2/m2/m) : Pmmn
Mazzite SubgroupZeolite Group.
MeieriteBa44Si66Al30O192Cl25(OH)33Iso. m3m(4/m32/m) : Im3m
MerlinoiteK5Ca2(Si23Al9)O64 · 24H2OOrth. mmm(2/m2/m2/m) : Immm
Montesommaite(K,Na)9Al9Si23O64 · 10H2OOrth. mm2 : Fdd2
Mordenite(Na2,Ca,K2)4(Al8Si40)O96 · 28H2OOrth.
MountainiteKNa2Ca2[Si8O19(OH)] · 6H2OMon. 2/m : P2/b
MutinaiteNa3Ca4Si85Al11O192 · 60H2OOrth. mmm(2/m2/m2/m) : Pnma
NabesiteNa2BeSi4O10 · 4H2OOrth. 222 : P212121
Natrolite SubgroupA subgroup of the Zeolite Group.
OffretiteKCaMg(Si13Al5)O36 · 15H2OHex. 6m2 : P6m2
PahasapaiteLi8(Ca,Li,K)10.5Be24(PO4)24 · 38H2OIso. 23 : I23
ParthéiteCa2(Si4Al4) O15 (OH)2 · 4H2OMon. 2/m : B2/b
Paulingite SubgroupPaulingite was originally described in 1960.
PerlialiteK9Na(Ca,Sr)[Al2Si4O12]6 · 15H2OHex. 6/mmm(6/m2/m2/m) : P6/mmm
Phillipsite Subgroup(Ca0.5,K,Na,Ba0.5)4-7[Al4-7Si12-9O32] . 12H2O
Pollucite(Cs,Na)2(Al2Si4O12) · 2H2OIso. m3m(4/m32/m) : Ia3d
RoggianiteCa2Be(OH)2Al2Si4O13 · 2.5H2OTet. 4/mmm(4/m2/m2/m) : I4/mcm
RongibbsitePb2(Si4Al)O11(OH) Mon. 2/m : B2/m
Stilbite SubgroupM6-7[Al8-9Si27-28O72] · nH2O
Terranovaite(Na,Ca)8(Si68Al12)O160 · 29H2OOrth.
Thomsonite SubgroupThe large majority of "thomsonite" is thomsonite-Ca.
ThornasiteNa12Th4+3(Si8O19)4 · 18H2OTrig. 3m : R3m
Tschernichite(Ca,Na2)[Al2Si4O12] · 4-8H2OTet. 4/mmm(4/m2/m2/m) : P4/mmm
TschörtneriteCa4(Ca,Sr,K,Ba)3Cu3[Al3Si3O12]4(OH)8 · nH2OIso. m3m(4/m32/m) : Fm3m
'UM1996-38-SiO:AlCaHNa'Na-Ca-Al-Si-O-H
'UM1999-33-SiO:AlHKNa'K7Na5Al12Si20O64 · 24H2O
'UM2002-40-SiO:AlCaHKMgNa'(Mg,Ca,Na,K)7.5(Al12.8Si51.2)O128 · 65H2OTet. 422 : P4122
'Unnamed (Ca analogue of Merlinoite)'(Ca,K,Na)5(Ca,Ba)2Al9Si23O64 · 23H2O ?
WairakiteCa(Al2Si4O12) · 2H2OMon. 2/m : B2/m
WeinebeneiteCaBe3(PO4)2(OH)2 · 4H2OMon. m : Bb
Wenkite(Ba,K)4(Ca,Na)6[(Si,Al)20O39(OH)2](SO4)3 · 0.5H2OHex. 6m2 : P62m
Wilancookite(Ba5Li2◻)Ba6Be24P24O96 · 26H2OIso. 23 : I23
WillhendersoniteKCa[Al3Si3O12] · 5H2OTric. 1 : P1
YugawaraliteCaAl2Si6O16 · 4H2OMon. m : Pb

Related Minerals - Strunz-mindat GroupingHide

8.DN.05NatrophosphateNa6+xHxF(PO4)2 · (19+x)H2OIso. m3m(4/m32/m) : Fd3c
8.DN.10IsoclasiteCa2(PO4)(OH) · 2H2OMon.
8.DN.15'Urphoite'U4+6(PO4)7(OH)3 · 4H2OMon.
8.DN.15LermontoviteU(PO4)(OH) · H2OOrth. mmm(2/m2/m2/m) : Ccca
8.DN.20VyacheslaviteU(PO4)(OH)Orth. mmm(2/m2/m2/m) : Cmca

Other InformationHide

Notes:
Insoluble in water or HCl.
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 LoomisiteHide

References for LoomisiteHide

Localities for LoomisiteHide

Showing 1 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.
USA (TL)
 
  • South Dakota
    • Pennington County
      • Keystone Mining District
        • Glendale
Miyawaki et al. (2022) +1 other reference
 
and/or  
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