Hundholmenite-(Y) Mineral Data

General Hundholmenite-(Y) Information

Chemical Formula:

(Y,REE,Ca,Na)15(Al,Fe+++)CaxAs+++1-x(Si,As+++++)Si6B3(O,F)48

Composition:

Molecular Weight = 2,521.06 gm

Sodium 0.91 % Na 1.23 % Na₂O

Calcium 5.56 % Ca 7.79 % CaO

La,Ce,Pr,Nd,Sm, 28.56 % RE 33.32 % REE₂O₃

Yttrium 21.16 % Y 26.87 % Y₂O₃

Aluminum 0.80 % Al 1.52 % Al₂O₃

Iron 0.55 % Fe 0.79 % Fe₂O₃

Silicon 7.52 % Si 16.09 % SiO₂

Boron 1.29 % B 4.14 % B₂O₃

Arsenic 2.23 % As 1.96 % As₂O₃ / 1.14 % As₂O₅

Oxygen 25.39 % O

Fluorine 6.03 % F 6.03 % F

- % F -2.54 % -O=F₂

______ ______

100.00 % 98.33 % = TOTAL OXIDE

Empirical Formula:

Y₆REE₅Ca₃NaAl_0.75Fe³⁺_0.25Ca_0.5As_0.5Si_0.75As_0.25Si₆B₃O₄₀F₈

Environment:

Found embedded in REE-bearing fluorite, in a granitic pegmatite. Vicanite group.

IMA Status:

Approved IMA 2006 (Dana # Added)

Locality:

Hundholmen, Tysfjord, Nordland, north Norway. Link to MinDat.org Location Data.

Name Origin:

Named for the locality.

Synonym:

IMA2006-005

Hundholmenite-(Y) Crystallography

Axial Ratios:

a:c = 1:2.53114

Cell Dimensions:

a = 10.675, c = 27.02, Z = 3; V = 2,666.56 Den(Calc)= 4.71

Crystal System:

Trigonal - Ditrigonal Pyramidal H-M Symbol (3m) Space Group: R 3m

$Help on X Ray Diffraction:$ X Ray Diffraction:

By Intensity(I/I_o): 2.972(1), 2.947(0.76), 2.924(0.66),3.114(0.43), 1.978(0.37), 2.681(0.36), 4.38(0.33), 3.095(0.29),

Physical Properties of Hundholmenite-(Y)

Color:

Pale brown.

Diaphaneity:

Transparent

Habit:

Inclusions - Generally found as inclusions in other minerals.

Habit:

Subhedral Crystals - Occurs as crystals which tend to exhibit a recognizable crystal shape.

Hardness:

5-6 - Between Apatite and Orthoclase

Luster:

Vitreous (Glassy)

Optical Properties of Hundholmenite-(Y)

Gladstone-Dale:

CI calc= 0.031 (Excellent) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.1599,KC= 0.1651
Ncalc = 1.78

Optical Data:

Uniaxial (-).

Calculated Properties of Hundholmenite-(Y)

Electron Density:

Bulk Density (Electron Density)=4.34 gm/cc
note: Specific Gravity of Hundholmenite-(Y) =4.71 gm/cc.

Fermion Index:

Fermion Index = 0.05
Boson Index = 0.95

Photoelectric:

PE_{Hundholmenite-(Y)}= 205.22 barns/electron
U=PE_{Hundholmenite-(Y)} x r_electron= 891.43 barns/cc.

Radioactivity:

GRapi = 28,195.18 (Gamma Ray American Petroleum Institute Units)
Concentration of Hundholmenite-(Y) per GRapi unit = 35.47 (PPM)

Hundholmenite-(Y) is Radioactive as defined in 49 CFR 173.403. Greater than 70 Bq / gram.

**Estimated Radioactivity from Hundholmenite-(Y)** - weak
Specimen Size Weight/Volume (Sphere) *	Calculated Activity Bequerols (Bq)	Calculated Activity Curies (Ci)	Estimated Activity GR(api)	Estimated Exposure (mRem**)/hr If Held in Hand For One Hour
1000 gm / 7.40 cm	642,028	1.74E-05	28,195.18	9.27
100 gm / 3.44 cm	64,203	1.74E-06	2,819.52	0.93
10 gm / 1.59 cm	6,420	1.74E-07	281.95	0.09
1 gm / 7.40 mm	642	1.74E-08	28.20	0.01
0.1 gm / 3.44 mm	64	1.74E-09	2.82	0.00
0.01 gm / 1.59 mm	6	1.74E-10	0.28	0.00
0.001 gm / 0.74 mm	1	1.74E-11	0.03	0.00

Weight of pure Hundholmenite-(Y) in grams (gm) and Calculated Diameter of a Sphere with a Density of 4.71 gm/cc.*
Goverment Estimate of Average Annual Exposure ( 360 mRem) **
Note: 10 microsieverts/hr = 1 mRem/hr **
Max Permissable Adult Dose 50,000 mRem/yr (hands), 15,000 mRem/yr (eyes)
Lethal Dose LD(50) Exposure 400,000 to 500,000 mRem
Estimated Thorium Activity ( 1.43 % Th) From Sum REE Elements (28.56 % REE)

Hundholmenite-(Y) Classification

Dana Class:

54.03.01.02 (54)Nesosilicate Borosilicates and Some Beryllosilicates

(54.03)Dana Type

(54.03.01)Vicanite Group

54.03.01.01 Vicanite-(Ce) (Ca,Ce,La,Th)15As(As0.5,Na0.5)FeSi6B4O40F7 R 3m 3m

54.03.01.02 Hundholmenite-(Y)! (Y,REE,Ca,Na)15(Al,Fe)CaxAs1-x(Si,As)Si6B3(O,F)48 R 3m 3m

54.03.01.03 Proshchenkoite-(Y)! (Y,REE,Ca,Na,Mn)15FeCa(P,Si)Si6B3(O,F)48 R 3m 3m

Strunz Class:

09.AJ.35 09 - SILICATES (Germanates)

09.A - Nesosilicates

09.AJ -Nesosilicates with BO3 triangles and/or B[4], Be[4] tetrahedra,

09.AJ.35 Okanoganite-(Y) (Na,Ca)3(Y,Ce)12Si6B2O27F14 R 3m 3m

09.AJ.35 Vicanite-(Ce) (Ca,Ce,La,Th)15As(As0.5,Na0.5)FeSi6B4O40F7 R 3m 3m

09.AJ.35 Hundholmenite-(Y)! (Y,REE,Ca,Na)15(Al,Fe)CaxAs1-x(Si,As)Si6B3(O,F)48 R 3m 3m

09.AJ.35 Proshchenkoite-(Y)! (Y,REE,Ca,Na,Mn)15FeCa(P,Si)Si6B3(O,F)48 R 3m 3m

Other Hundholmenite-(Y) Information

References:

NAME( MinMag v71:179) PHYS. PROP.(MinMag v71:179) OPTIC PROP.(MinMag v71:179)

See Also:

Links to other databases for Hundholmenite-(Y) :
1 - Am. Min. Crystal Structure Database
2 - Athena
3 - GeoScienceWorld
4 - Google Images
5 - Google Scholar
6 - MinDAT
7 - Mineralienatlas (Deutsch)
8 - Online Mineral Museum
9 - QUT Mineral Atlas
10 - Ruff.Info

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Hundholmenite-(Y)

(Y,REE,Ca,Na)15(Al,Fe+++)CaxAs+++1-x(Si,As+++++)Si6B3(O,F)48
Dana No: 54.03.01.02 Strunz No: 09.AJ.35
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