Mcguinnessite Mineral Data

General Mcguinnessite Information

Chemical Formula:

(Mg,Cu)2(CO3)(OH)2

Composition:

Molecular Weight = 162.25 gm

Magnesium 22.47 % Mg 37.26 % MgO

Copper 19.58 % Cu 24.51 % CuO

Hydrogen 1.24 % H 11.10 % H₂O

Carbon 7.40 % C 27.12 % CO₂

Oxygen 49.30 % O

______ ______

100.00 % 100.00 % = TOTAL OXIDE

Empirical Formula:

Mg_1.5Cu_0.5(CO₃)(OH)₂

Environment:

Occurs in serpentinized peridotite.

IMA Status:

Approved IMA 1981

Locality:

Miners Ridge, Red Mountain, 15 miles SE of Ukiah, Mendocino County, California, USA. Link to MinDat.org Location Data.

Name Origin:

Named for Albert L. McGuinness (1926-1990), mineral dealer, San Mateo, California, USA>

Name Pronunciation:

Mcguinnessite + Pronunciation

Mcguinnessite Image

Images:

Mcguinnessite

Comments: Cotton ball clusters of vivid blue mcguinnessite crystals on matrix.
Location: Miners Ridge, Red Mountain, Mendocino County, California, USA. Scale: Not Given.
© Lou Perloff / Photo Atlas of Minerals

Images:

Vuagnatite Mcguinnessite

Comments: Translucent colorless vuagnatite microcrystals with mcguinnessite.
Location: Near Red Mountain, Mendocino County, California, USA. Scale: See Photo.
© Jeff Weissman / Photographic Guide to Mineral Species

Mcguinnessite Crystallography

Axial Ratios:

a:b:c =0.7824:1:0.2813

Cell Dimensions:

a = 9.398, b = 12.011, c = 3.379, Z = 4; beta = 93.28° V = 380.79 Den(Calc)= 2.83

Crystal System:

Monoclinic - Prismatic H-M Symbol (2/m) Space Group: P 2/a or P 2₁/a

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

By Intensity(I/I_o): 6.015(1), 3.694(0.67), 2.14(0.3),2.53(0.25), 2.33(0.2), 5.05(0.2), 3(0.1), 7.4(0.1),

Physical Properties of Mcguinnessite

Color:

Blue green, Green, White.

Density:

3.02 - 3.22, Average = 3.12

Diaphaneity:

Transparent to Translucent

Fracture:

Brittle - Generally displayed by glasses and most non-metallic minerals.

Habit:

Spherical - Spherical, rounded aggregates.

Hardness:

2.5 - Finger Nail

Luster:

Vitreous - Silky

Optical Properties of Mcguinnessite

Gladstone-Dale:

CI meas= -0.039 (Good) - where the CI = (1-KPDmeas/KC)
CI calc= -0.146 (Poor) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.2419,KPDmeas= 0.2194,KC= 0.2112
Ncalc = 1.6 - 1.68

Optical Data:

Biaxial (-), a=1.596-1.602, b=1.724-1.73, g=1.724-1.732, bire=0.1280-0.1300

Pleochroism (x):

very pale green.

Pleochroism (y):

light blue green.

Pleochroism (z):

light blue green.

Calculated Properties of Mcguinnessite

Electron Density:

Bulk Density (Electron Density)=3.10 gm/cc
note: Specific Gravity of Mcguinnessite =3.12 gm/cc.

Fermion Index:

Fermion Index = 0.02
Boson Index = 0.98

Photoelectric:

PE_{Mcguinnessite}= 8.94 barns/electron
U=PE_{Mcguinnessite} x rElectron Density= 27.69 barns/cc.

Radioactivity:

GRapi = 0 (Gamma Ray American Petroleum Institute Units)
Mcguinnessite is Not Radioactive

Mcguinnessite Classification

Dana Class:

16a.03.01.05 (16a)Carbonates - Hydroxyl or Halogen

(16a.03)where (A B)2 (XO3) Zq

(16a.03.01)Rosasite Group

16a.03.01.01 Rosasite (Cu,Zn)2(CO3)(OH)2 P 2₁/a 2/m

16a.03.01.02 Glaukosphaerite (Cu,Ni)2(CO3)(OH)2 P 2₁/a 2/m

16a.03.01.03 Kolwezite (Cu,Co)2(CO3)(OH)2 P1 or P1 Tri

16a.03.01.04 Zincrosasite (Zn,Cu)2(CO3)(OH)2 P 2₁/a 2/m

16a.03.01.05 Mcguinnessite (Mg,Cu)2(CO3)(OH)2 P 2/a or P 2₁/a 2/m

Strunz Class:

05.BA.10 05 - CARBONATES (NITRATES)

05.B - Carbonates with additional anions, without H2O

05.BA -With Cu, Co, Ni, Zn, Mg, Mn

05.BA.10 Nullaginite Ni2(CO3)(OH)2 P 2₁/m,P 2₁ Mono

05.BA.10 Georgeite Cu5(CO3)3(OH)4•6(H2O) None

05.BA.10 Malachite Cu2(CO3)(OH)2 P 2₁/a 2/m

05.BA.10 Glaukosphaerite (Cu,Ni)2(CO3)(OH)2 P 2₁/a 2/m

05.BA.10 Mcguinnessite (Mg,Cu)2(CO3)(OH)2 P 2/a or P 2₁/a 2/m

05.BA.10 Kolwezite (Cu,Co)2(CO3)(OH)2 P1 or P1 Tri

05.BA.10 Pokrovskite Mg2(CO3)(OH)2•0.5(H2O) P 2₁/a 2/m

05.BA.10 Rosasite (Cu,Zn)2(CO3)(OH)2 P 2₁/a 2/m

05.BA.10 Zincrosasite (Zn,Cu)2(CO3)(OH)2 P 2₁/a 2/m

05.BA.10 Chukanovite! Fe2(CO3)(OH)2 P 2₁/a 2/m

Other Mcguinnessite Information

References:

NAME( MinRec) PHYS. PROP.(Dana8) OPTIC PROP.(Dana8)

See Also:

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

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Print or Cut-and-Paste your Mcguinnessite Specimen Label here :

Mcguinnessite

(Mg,Cu)2(CO3)(OH)2
Dana No: 16a.03.01.05 Strunz No: 05.BA.10
Locality:

Notes:

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