Hewettite Mineral Data +

Mineral of the Month Club

General Hewettite Information
Chemical Formula:	CaV6O16·9(H2O)
Composition:	Molecular Weight = 763.85 gm
	Calcium    5.25 %  Ca    7.34 % CaO
	Vanadium  40.01 %  V    71.43 % V2O5
	Hydrogen   2.38 %  H    21.23 % H2O
	Oxygen    52.36 %  O
	______        ______
	100.00 %      100.00 % = TOTAL OXIDE
Empirical Formula:	CaV5+6O16·9(H2O)
IMA Status:	Valid Species (Pre-IMA) 1914
Locality:	Link to MinDat.org Location Data.
Synonym:	ICSD 203169
	PDF 35-564
Hewettite Image
Images:	Hewettite   Fervanite Comments: Spherical aggregate of acicular microcrystals of fervanite with blocky hewettite. Location: Gold Quarry Mine, Carlin Trend, Eureka County, Nevada, USA. Scale: See Photo. © Jeff Weissman / Photographic Guide to Mineral Species
Images:	Hewettite Comments: Red sub-metallic fibrous mats of hewettite on matrix. Location: Cactus Rat Mine, Thompson's District, Grand Count, Utah, USA. Scale: See Photo. © Jeff Weissman / Photographic Guide to Mineral Species
Hewettite Crystallography
Axial Ratios:	a:b:c =3.503:1:3.1953
Cell Dimensions:	a = 12.25, b = 3.497, c = 11.174, Z = 1; beta = 97.25° V = 474.85 Den(Calc)= 2.67
Crystal System:	Monoclinic - PrismaticH-M Symbol (2/m) Space Group: P 2/m
X Ray Diffraction:	By Intensity(I/Io): 11.03(1), 5.53(0.35), 2.1636(0.25),
Crystal Structure: Mouse drag1 - LMB Manipulate Structure drag2 - RMB Resize/Rotate Keyboard S - Stereo Pair on/off H - Help Screen I - Data Info A - Atoms On/Off P - Polyhedra On/Off B - Bonds On/Off Help on Above	Evans H T , The Canadian Mineralogist , 27 (1989) p.181-188, The crystal structure of hewettite, Note: sample Weeks number W-220-54, Locality: Colorado Plateau, USA
Physical Properties of Hewettite
Color:	Red.
Density:	2.5 - 2.6, Average = 2.54
Habit:	Acicular - Occurs as needle-like crystals.
Luminescence:	Non-fluorescent.
Luster:	Silky
Magnetism:	Nonmagnetic
Streak:	brownish red
Optical Properties of Hewettite
Gladstone-Dale:	CI meas= -0.315 (Poor) - where the CI = (1-KPDmeas/KC) CI calc= -0.256 (Poor) - where the CI = (1-KPDcalc/KC) KPDcalc= 0.4151,KPDmeas= 0.4346,KC= 0.3305
Optical Data:	Biaxial (-), a=1.77, b=2.18, g=2.35-2.4, bire=0.5800-0.6300
Calculated Properties of Hewettite
Electron Density:	relectron=2.63 gm/cc note: rHewettite =2.67 gm/cc.
Fermion Index	Fermion Index = 0.00132 Boson Index = 0.99868
Photoelectric:	PEHewettite = 8.20 barns/electron U=PEHewettite x relectron= 21.57 barns/cc.
Radioactivity:	GRapi = 0 (Gamma Ray American Petroleum Institute Units) Hewettite is Not Radioactive
Hewettite Classification
Dana Class:	47.3.1.1 (47)Vanadium Oxysalts
	(47.3)(Hydrated)
	(47.3.1)Dana Group
	47.3.1.1 Hewettite CaV6O16·9(H2O) P 2/m 2/m
	47.3.1.2 Metahewettite CaV6O16·3(H2O) A2/m 2/m
	47.3.1.3 Barnesite Na2V6O16·3(H2O) P 2/m 2/m
	47.3.1.4 Hendersonite Ca1.3V6O16·6(H2O) Pnam 2/m 2/m 2/m
	47.3.1.5 Grantsite Na4CaxV2xV12-2xO32·8(H2O) C 2/m 2/m
Strunz Class:	IV/G.12-40 IV - Oxides
	IV/G - Vanadiumoxides (with V4+/5+) Layered vanadates. Typical Vanadiumbronzes
	IV/G.12 - Barnessite - Metahewettite series
	IV/G.12-10 Barnesite Na2V6O16·3(H2O) P 2/m 2/m
	IV/G.12-20 Grantsite Na4CaxV2xV12-2xO32·8(H2O) C 2/m 2/m
	IV/G.12-30 Hendersonite Ca1.3V6O16·6(H2O) Pnam 2/m 2/m 2/m
	IV/G.12-40 Hewettite CaV6O16·9(H2O) P 2/m 2/m
	IV/G.12-50 Metahewettite CaV6O16·3(H2O) A2/m 2/m
Other Hewettite Information
References:	PHYS. PROP.(Enc. of Minerals,2nd ed.,1990) OPTIC PROP.(Enc. of Minerals,2nd ed.,1990)
See Also:	Links to other databases for Hewettite : 1 -Am. Min. Crystal Structure Database 2 -Athena 3 - EUROmin Project 4 -Google Images 5 -Google Scholar 6 -Handbook of Mineralogy (UofA) 7 -MinDAT 8 -MinMax(Deutsch) 9 -MinMax(English) 10 -Mineralienatlas (Deutsch) 11 -QUT Mineral Atlas 12 - WWW-MINCRYST 13 -École des Mines de Paris Search for Hewettite using:   Web webmineral.com [ALTAVISTA] [AOL] [All-The-Web] [HotBot] [Ixquick] [MAMMA] [MSN.COM] [Netscape] [Scirus] [Teoma] [Wikipedia] [YAHOO] Visit our Advertisers for Hewettite : AA Mineral Specimens B & L Fine Minerals Crystal Vaults Dan Weinrich Fine Minerals Dan Weinrich Auctions e-Rocks Auctions Excalibur Minerals Exceptional Minerals Fabre Minerals Greenside Minerals Heliodor John Betts Fine Minerals Mason's Minerals Mineral News Mineral of the Month Club MineralsWeb Fine Minerals Rockshop.cz T G Fine Minerals Wrights Rock Shop Translate Hewettite Mineral Data : Ask about Hewettite here : Ask-A-Mineralogist from the Mineralogical Society of America Mindat.org's Discussion Groups Original Rockhounds Discussion Group Rockhounds Discussion Group on Yahoo Groups Mineral Discussion Forum from Fabre Minerals - also available in Español Print or Cut-and-Paste your Hewettite Specimen Label here : Hewettite CaV6O16·9(H2O) Dana No: 47.3.1.1 Strunz No: IV/G.12-40 Locality:   Notes: