Mindat Logo
Home Page Log In Message Board The Mindat Directory
Register Search Pages Chat Now! (2 online) Mindat Auctions

Medaite

Big Photo

Molinello Mine, Graveglia Valley, Ne, Genova Province, Liguria, Italy
© Stephan Wolfsried

Show Medaite Photos (10)
Formula:
(Mn,Ca)
 
6
(V,As)Si
 
5
O
 
18
OH
System:MonoclinicColour:Brownish-red
Name:For Dr. Francesco Meda, an amateur mineralogist from Turin.
This page provides mineralogical data about Medaite.

Classification of Medaite

IMA status:Approved
Strunz 8th edition ID:8/C.34-14
Nickel-Strunz 10th (pending) edition ID:9.BJ.30

9 : SILICATES (Germanates)
B : Sorosilicates
J : Sorosilicates with Si3O10, Si4O11, etc. anions; cations in octahedral [6] and greater coordination
Dana 8th edition ID:57.4.1.1

57 : SOROSILICATES Si3O10 Groups and Larger Noncyclic Groups
4 : Insular Si3O10 and Larger Noncyclic Groups with groups with 6 or more tetrahedra
Hey's CIM Ref.:17.7.5

17 : Silicates Containing other Anions
7 : Silicates with vanadate, arsenate or antimonate
mindat.org URL:http://www.mindat.org/min-2624.html
Please feel free to link to this page.

Type Occurrence of Medaite

Type Locality:Molinello Mine, Graveglia Valley, Ne, Genova Province, Liguria, Italy
Place of Conservation of Type Material:Institute of Mineralogy, Milan, Mineral Museums of Universities of Rome and Oslo, Norway.
Year of Discovery:1982
Geological Setting of type material:Manganese mine.

Physical Properties of Medaite

Lustre:Sub-Adamantine
Diaphaneity (Transparency):Translucent
Colour:Brownish-red
Cleavage:Distinct/Good
{100}
Parting:Distinct normal to elongation
Density (measured):3.65 - 3.75 g/cm3
Density (calculated):3.7 g/cm3

Crystallography of Medaite

Crystal System:Monoclinic
Cell Parameters:a = 6.71Å, b = 28.94Å, c = 7.57Å
β = 95.4°
Ratio:a:b:c = 0.232 : 1 : 0.262
Unit Cell Volume:V 1,463.47 ų (Calculated from Unit Cell)

Optical Data of Medaite

Type:Biaxial (+)
RI values: nα = 1.770 nβ = 1.780 nγ = 1.800
2V:Measured: 71° , Calculated: 72°
Maximum Birefringence:δ = 0.030

Chart shows birefringence interference colour range (at 30µm thickness) and does not take into account mineral colouration.
Surface Relief:Very High
Dispersion:r > v distinct
Pleochroism:Weak
Comments:Dark to lighter orange

Chemical Properties of Medaite

Formula:
(Mn,Ca)
 
6
(V,As)Si
 
5
O
 
18
OH
Essential elements:H, Mn, O, Si, V
All elements listed in formula:As, Ca, H, Mn, O, Si, V
Common Impurities:Fe,H2O

Relationship of Medaite to other Species

Related Minerals - Nickel-Strunz Grouping):

- +
9.BJ.05Orientite
Ca
 
2
MnMn
 
2
Si
 
3
O
 
10
(OH)
 
4
9.BJ.10Rosenhahnite
HCa
 
3
[Si
 
3
O
 
9
(OH)]
9.BJ.15Trabzonite
Ca
 
4
Si
 
3
O
 
10
·2H
 
2
O
9.BJ.20Thalénite-(Y)
Y
 
3
Si
 
3
O
 
10
(OH)
9.BJ.20Fluorthalénite-(Y)
Y
 
3
Si
 
3
O
 
10
F
9.BJ.25Tiragalloite
Mn
 
4
AsSi
 
3
O
 
12
(OH)
9.BJ.35Ruizite
Ca
 
2
Mn
3+
2
[(OH)
 
2
|H
 
2
Si
 
4
O
 
13
] · 2H
 
2
O
9.BJ.40Ardennite-(As)
Mn
2+
4
[(Al,Mg)
 
6
][(OH)
 
6
|(AsO
 
4
,VO
 
4
)|(SiO
 
4
)
 
2
|Si
 
3
O
 
10
]
9.BJ.40Ardennite-(V)
Mn
2+
4
[Al
 
4
(Mg,Al,Fe
3+
 
,Mn
3+
 
)
 
2
][(OH)
 
6
|(VO
 
4
,SiO
 
4
)|(SiO
 
4
)
 
2
|Si
 
3
O
 
10
]
9.BJ.45Kilchoanite
Ca
 
3
Si
 
2
O
 
7
9.BJ.50Kornerupine
Mg
 
3
Al
 
6
(Si,Al,B)
 
5
O
 
21
(OH)
9.BJ.50Prismatine
([ ],Fe,Mg)(Mg,Al,Fe)
 
5
Al
 
4
Si
 
2
(Si,Al)
 
2
(B,Si,Al)(O,OH,F)
 
22
9.BJ.55Zunyite
Al
 
13
Si
 
5
O
 
20
(OH,F)
 
18
Cl
9.BJ.60Hubeite
Ca
 
2
Mn
2+
 
Fe
3+
 
[HSi
 
4
O
 
13
] · 2H
 
2
O
9.BJ.65Cassagnaite
(Ca,Mn
2+
 
)
 
4
(Fe
3+
 
,Mn
3+
 
,Al)
 
4
(V
3+
 
,Mg,Al)
 
2
[(O,OH)
 
4
|(OH)
 
4
|(SiO
 
4
)
 
2
|Si
 
3
O
 
10
]
Related Minerals - Hey's Index Grouping:

- +
17.7.1Suzukiite
BaVSi
 
2
O
 
7
17.7.2Franciscanite
Mn
2+
6
(V
5+
 
,[])
 
2
[(O,OH)
 
3
|SiO
 
4
]
 
2
17.7.3Kurumsakite
(Zn,Ni,Cu)
 
8
Al
 
8
V
 
2
Si
 
5
O
 
35
·27H
 
2
O (or near)
17.7.4Ardennite-(As)
Mn
2+
4
[(Al,Mg)
 
6
][(OH)
 
6
|(AsO
 
4
,VO
 
4
)|(SiO
 
4
)
 
2
|Si
 
3
O
 
10
]
17.7.6Johninnesite
Na
 
2
Mn
2+
9
Mg
 
7
(OH)
 
8
[AsO
 
4
]
 
2
[Si
 
6
O
 
17
]
 
2
17.7.7Tiragalloite
Mn
 
4
AsSi
 
3
O
 
12
(OH)
17.7.8Dixenite
CuMn
2+
14
Fe
2+
 
[(OH)
 
6
|(AsO
 
3
)
 
5
|AsO
 
4
|(SiO
 
4
)
 
2
]
17.7.9Asbecasite
Ca
 
3
(Ti,Sn
4+
 
)Be
 
2
[(AsO
 
3
)
 
3
|SiO
 
4
]
 
2
17.7.10Mcgovernite
(Mn,Mg,Zn)
 
273
As
3+
~12
As
5+
~30
Si
 
~42
O
 
324
(OH)
 
252
17.7.11Kraisslite
(Mn
2+
 
,Mg)
 
24
Zn
 
4
[(OH)
 
12
|(AsO
 
4
)
 
4
|(SiO
 
4
)
 
8
]
17.7.12Schallerite
(Mn,Fe)
 
16
Si
 
12
As
 
3
O
 
36
(OH)
 
17
17.7.13Nelenite
(Mn,Fe)
 
16
(Si
 
12
O
 
30
)(OH)
 
14
[As
3+
3
O
 
6
(OH)
 
3
]
17.7.14Kolicite
Mn
2+
7
Zn
 
4
[(OH)
 
8
|(AsO
 
4
)
 
2
|(SiO
 
4
)
 
2
]
17.7.15Yeatmanite
Mn
2+
7
Zn
 
8
Sb
5+
2
[O
 
3
|SiO
 
4
]
 
4
17.7.16Welshite
Ca
 
4
Mg
 
9
Sb
 
3
O
 
4
[Si
 
6
Be
 
3
AlFe
 
2
O
 
36
]
17.7.17Katoptrite
(Mn
2+
 
,Mg)
 
13
(Al,Fe
3+
 
)
 
4
Sb
5+
2
[O
 
10
|SiO
 
4
]
 
2
17.7.18Parwelite
Mn
 
10
Sb
 
2
As
 
2
Si
 
2
O
 
24
17.7.19Långbanite
(Mn
2+
 
,Ca)
 
4
(Mn
3+
 
,Fe
3+
 
)
 
9
Sb
5+
 
[O
 
8
|SiO
 
4
]
 
2
17.7.20Chapmanite
Fe
3+
2
Sb
3+
 
[OH|(SiO
 
4
)
 
2
]
17.7.21Cervandonite-(Ce)
(Ce,Nd,La)(Fe
3+
 
,Fe
2+
 
,Ti,Al)
 
3
O
 
2
(Si
 
2
O
 
7
)(As
3+
 
O
 
3
)(OH)

Other Names for Medaite

Synonyms:
IMA1979-062
Other Languages:
German:Medait
Russian:Медаит
Spanish:Medaita

Other Information

Health Warning:No information on health risks for this material has been entered into the database. You should always treat mineral specimens with care.

References for Medaite

Reference List:American Mineralogist (1982): 67: 85-89.

Acta Crystallographica: 37: 1972-1978.

Internet Links for Medaite

Search Engines:
  • Look for Medaite on Google
  • Look for Medaite images on Google
    • External Links:
  • Look for Medaite on Webmineral
  • Look for Medaite on Athena Mineralogy
  • Look for Medaite on Wikipedia
  • Look for Medaite on Mineralien Atlas
  • Raman and XRD data at RRUFF project
  • American Mineralogist Crystal Structure Database
  • Search for Medaite in the Natural History Museum (London) online catalogue
  • Medaite details from Handbook of Mineralogy (PDF)
    • Mineral Dealers:
  • Rare and Unusual minerals at Mineralogical Research Company
  • SpiriferMinerals.com - high quality specimens
  • Fabre Minerals - search for Medaite specimens
  • Wendel Minerals - Auktion & Shop
  • The Arkenstone - Fine Minerals
  • Mineral Classics - Worldwide Collector Quality Minerals and Gems
  • Buy fine minerals and gemstones from Pala International
  • Buy from David K Joyce minerals
  • Find Medaite on www.crystalclassics.co.uk
  • Buy Fine Minerals from mineralsweb.com
  • DAKOTA MATRIX offers Cabinet and Rare Species from Worldwide Localities.
  • Wright's Rock Shop - excellent mineral specimens since 1970
    • Jobs:
  • Mining & Geology Jobs

    • Page Sponsor

    Sponsorship:This page is currently not sponsored. Click here to sponsor this page.

    Localities for Medaite

    (TL) indicates type locality. ? indicates mineral may be doubtful at this locality. All other localities listed without reference should be considered as uncertain and unproven until references can be found.
    Italy
     
    • Liguria
      • Genova Province
        • Ne
          • Graveglia Valley
    		Redazionale (2005): Sistematica ligure: resoconto 2005. Notiziario di Mineralogia del Ferrania Club, 19 , 3-5.
    [Amer.Min.(1982) 67, 85-89; MinRec 32:355]
            • Reppia
    		Rivista Mineralogica Italiana, (4), 131
    Switzerland
     
    • Grischun (Grisons; Graubünden)
      • Hinterrhein Valley
        • Ferrera Valley
          • Ausserferrera
    		J. Brugger et al.: Can. Mineral. 41:1423-1431 (2003); American Mineralogist: 91: 937-943.
    Mineral and/or Locality
    Google
     
    www.mindat.org Web
    Copyright © Jolyon Ralph and Ida Chau 1993-2009. Site Map. Locality, mineral & photograph data are the copyright of the individuals who submitted them.Further information contact the Site hosted & developed by Jolyon Ralph. Mindat.org is an online information resource dedicated to providing free mineralogical information to all. Mindat relies on the contributions of hundreds of members and supporters. If you would like to add information to improve the quality of our database, then click here to register. Current server date and time: 9th Oct 2009 10:01:49