Chalcophanite Mineral Data

General Chalcophanite Information

Chemical Formula: (Zn,Fe++,Mn++)Mn++++3O7•3(H2O) Composition: Molecular Weight = 459.22 gm    Manganese  40.68 %  Mn    6.18 % MnO / 56.79 % MnO₂    Zinc       17.09 %  Zn   21.27 % ZnO    Iron        6.08 %  Fe    7.82 % FeO    Hydrogen    1.32 %  H    11.77 % H₂O    Oxygen     34.84 %  O              ______        ______               100.00 %      103.83 % = TOTAL OXIDE Empirical Formula: Zn_1.2Fe²⁺_0.5Mn²⁺_0.4Mn⁴⁺₃O₇•3(H₂O) Environment: Common component of the weathered zone above Zn-Mn base metal deposits. IMA Status: Valid Species (Pre-IMA) 1875 Locality: Sterling Hill, near Ogdensburg, Sussex Co., New Jersey, USA. Link to MinDat.org Location Data. Name Origin: From the Greek for "copper" and "to appear," for the mineral's change in color on ignition. Name Pronunciation: Chalcophanite Synonym: Hydrofranklinite   ICSD 202700   PDF 15-807  

Chalcophanite Image

Images:

Chalcophanite Comments: Large mass of rounded gray-black chalcophanite. Location: Sterling Mine, Sterling Hill, Ogdensburg, Franklin Mining District, Sussex Co., New Jersey, USA. Scale: 14x11x7 cm. © John Betts - Fine Minerals

Chalcophanite Crystallography

Axial Ratios: a:c = 1:2.76038 Cell Dimensions: a = 7.533, c = 20.794, Z = 5; V = 1,021.89 Den(Calc)= 3.73 Crystal System: Trigonal - RhombohedralH-M Symbol ( 3) Space Group: R 3 X Ray Diffraction: By Intensity(I/I_o): 6.96(1), 3.5(0.6), 4.08(0.5), Forms:

Mouse
Dbl Clk - Start-Stop Rotation
RMB - Cycle Display Modes
Drag1 - Manipulate Crystal
Drag2 - Resize
Keyboard
S - Stereo
I - Indicies
<space> - Start-Stop Rotation
F - Fit to Screen
M - Menu
Help on Above

Forms: ( 1 0 1) ( 0 0 1) Warning: this large pop-up is very compute intensive and may not work well with some computers.

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

Post J E , Appleman D E , American Mineralogist , 73 (1988) p.1401-1404, Chalcophanite, ZnMn3O7.3(H2O): New crystal-structure determinations, Locality: Bisbee, Arizona, Note: U(1,2) of O3 altered to match symmetry constraints, Note: H positions determined by energy modelling View Additional jPOWD Structure files for Chalcophanite [1]

 

Physical Properties of Chalcophanite

Cleavage: {???} Perfect Color: Blue, Bluish black, Black. Density: 3.91 Diaphaneity: Opaque Fracture: Flexible - Flexible fragments. Habit: Foliated - Two dimensional platy forms. Habit: Stalactitic - Shaped like pendant columns as stalactites or stalagmites (e.g. calcite). Hardness: 2.5 - Finger Nail Luminescence: Non-fluorescent. Luster: Metallic Magnetism: Nonmagnetic Streak: brown  

Optical Properties of Chalcophanite

Dichroism (e): deep red. Dichroism (w): opaque black. Gladstone-Dale: CI meas= -0.361 (Poor) - where the CI = (1-KPDmeas/KC)
CI calc= -0.426 (Poor) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.4625,KPDmeas= 0.4412,KC= 0.3243
Ncalc = 2.21 - 2.27 Optical Data: Uniaxial (-), e=2.72, w=2.73, bire=0.0100. RL Anisotrophism: Very strong. RL Color: White with deep red internal reflections. RL Pleochroism: Very strong, in gray and white. Reflectivity Standardized Intensity (100%) Reflection Spectra of Chalcophanite in Air

λ	R1	R2		∑ R1(λ)	∑ R2(λ)
400 nm	11.40	38.00

     420 nm   11.00   36.60 
 440 nm   10.60   35.20 
 460 nm   10.30   33.80 
 480 nm   10.00   32.20 
 500 nm    9.80   30.70 
 520 nm    9.80   29.20 
 540 nm    9.70   28.00 
 560 nm    9.50   26.90 
 580 nm    9.30   26.20 
 600 nm    9.30   25.80 
 620 nm    9.20   25.40 
 640 nm    9.20   24.80 
 660 nm    9.00   24.40 
 680 nm    8.90   24.00 
 700 nm    8.90   23.80