Help mindat.org|Log In|Register|
Home PageMindat NewsThe Mindat ManualHistory of MindatCopyright StatusManagement TeamContact UsAdvertise on Mindat
Donate to MindatSponsor a PageSponsored PagesTop Available PagesMindat AdvertisersAdvertise on Mindat
Minerals by PropertiesMinerals by ChemistryAdvanced Locality SearchRandom MineralSearch by minIDLocalities Near MeSearch ArticlesSearch GlossaryMore Search Options
Search For:
Mineral Name:
Locality Name:
Keyword(s):
 
The Mindat ManualAdd a New PhotoRate PhotosLocality Edit ReportCoordinate Completion ReportAdd Glossary Item
StatisticsThe ElementsMember ListBooks & MagazinesMineral Shows & EventsThe Mindat DirectoryHow to Link to MindatDevice Settings
Photo SearchPhoto GalleriesNew Photos TodayNew Photos YesterdayMembers' Photo GalleriesPast Photo of the Day Gallery

Coutinhoite

This page is currently not sponsored. Click here to sponsor this page.
Formula:
ThxBa(1-2x)(UO2)2Si5O13 · (H2O)1+y (0 < x < 0.5 and 0 < y < (2+x))
Colour:
yellow
Lustre:
Waxy, Silky
Hardness:
2
Crystal System:
Orthorhombic
Name:
For Jose Moacyr Vianna Couthino, Professor of Mineralogy, Institute of Geological Sciences, Sao Paulo, Brazil.
This page provides mineralogical data about Coutinhoite.


Hide all sections | Show all sections

Classification of CoutinhoiteHide

Approved
Approval Year:
2003
9.AK.30

9 : SILICATES (Germanates)
A : Nesosilicates
K : Uranyl neso- and polysilicates

Physical Properties of CoutinhoiteHide

Waxy, Silky
Transparency:
Transparent, Translucent
Colour:
yellow
Streak:
yellow
Hardness:
Tenacity:
Brittle

Optical Data of CoutinhoiteHide

Type:
Biaxial (-)
RI values:
nα = 1.620 nβ = 1.627 nγ = 1.629
2V:
Measured: 40° , Calculated: 56°
Max Birefringence:
δ = 0.009
Image shows birefringence interference colour range (at 30µm thickness)
and does not take into account mineral colouration.
Surface Relief:
Moderate
Dispersion:
strong r
Pleochroism:
Visible
Comments:
Z>Y, X yellow

Chemical Properties of CoutinhoiteHide

Formula:
ThxBa(1-2x)(UO2)2Si5O13 · (H2O)1+y (0 < x < 0.5 and 0 < y < (2+x))
IMA Formula:
ThxBa1-2x(UO2)2Si5O13 · 3H2O

Crystallography of CoutinhoiteHide

Crystal System:
Orthorhombic
Cell Parameters:
a = 14.1675 Å, b = 14.1935 Å, c = 35.754 Å
Ratio:
a:b:c = 0.998 : 1 : 2.519
Unit Cell V:
7189.7 ų
Z:
16
Morphology:
Scales and flakes
Twinning:
Not observed

Type Occurrence of CoutinhoiteHide

General Appearance of Type Material:
Fine grained yellow massive material. Flaky crystals 10 microns long by 0.5 microns thick.
Place of Conservation of Type Material:
Geoscience Museum, Institute of Geosciences, University of Sao Paulo, Brazil
Geological Setting of Type Material:
Secondary hydrothermal mineral in a pegmatite

Synonyms of CoutinhoiteHide

Other Language Names for CoutinhoiteHide

Related Minerals - Nickel-Strunz GroupingHide

9.AK.05Soddyite(UO2)2SiO4 · 2H2OOrth.
9.AK.10CuprosklodowskiteCu(UO2)2(SiO3OH]2 · 6H2OTric. 1 : P1
9.AK.10OursiniteCo(UO2)2(SiO3OH)2 · 6H2OOrth. mmm (2/m 2/m 2/m) : Cmca
9.AK.10SklodowskiteMg(UO2)2(SiO3OH)2 · 6H2OMon. 2/m : B2/m
9.AK.15Boltwoodite(K,Na)(UO2)(SiO3OH) · 1.5H2OMon. 2 : P21
9.AK.15KasolitePb(UO2)[SiO4] · H2OMon. 2/m : P21/b
9.AK.15NatroboltwooditeNa(UO2)(SiO3OH) · H2O
9.AK.15Uranophane-βCa(UO2)2(SiO3OH)2 · 5H2OMon.
9.AK.15UranophaneCa(UO2)2(SiO3OH)2 · 5H2OMon. 2 : P21
9.AK.15Beta-UranophaneCa(UO2)2(SiO3OH)2 · 5H2O
9.AK.20Swamboite-(Nd)Nd0.333[(UO2)(SiO3OH)](H2O)∼2.5Mon.
9.AK.25HaiweeiteCa(UO2)2[Si5O12(OH)2] · 6H2OMon.
9.AK.25MetahaiweeiteCa(UO2)2Si6O15 · nH2O
9.AK.25RanquiliteCa(UO2)2[Si5O12(OH)2] · 6H2O
9.AK.30WeeksiteK2(UO2)2(Si5O13) · 4H2OOrth.
9.AK.35UrsiliteMg4(UO2)4(Si2O5)5.5(OH)5 · 13H2OOrth.
9.AK.35MagnioursiliteMg4(UO2)4(Si2O5)5(OH)6 · 20H2O
9.AK.35CalcioursiliteCa4(UO2)4(Si2O5)5(OH)6 · 15H2O
9.AK.40UranosiliteUO3 · 7SiO2Orth.

Fluorescence of CoutinhoiteHide

Other InformationHide

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

References for CoutinhoiteHide

Reference List:
Sort by Year (asc) | by Year (desc) | by Author (A-Z) | by Author (Z-A)
Atencio, D., Carvalho, F. M. S. & Matioli, P. A. (2004): Coutinhoite, a new thorium uranyl silicate hydrate, from Urucum mine, Galileia, Minas Gerais, Brazil. American Mineralogist: 89: 721-724.

Internet Links for CoutinhoiteHide

Localities for CoutinhoiteHide

This map shows a selection of localities that have latitude and longitude coordinates recorded. Click on the symbol to view information about a locality. The symbol next to localities in the list can be used to jump to that position on the map.

Locality ListHide

- This locality has map coordinates listed. - This locality has estimated coordinates. ⓘ - Click for further information on this occurrence. ? - Indicates mineral may be doubtful at this locality. - Good crystals or important locality for species. - World class for species or very significant. (TL) - Type Locality for a valid mineral species. (FRL) - First Recorded Locality for everything else (eg varieties). Struck out - Mineral was erroneously reported from this locality. Faded * - Never found at this locality but inferred to have existed at some point in the past (eg from pseudomorphs.)

All localities listed without proper references should be considered as questionable.
Brazil (TL)
 
  • Minas Gerais
    • Galiléia
American Mineralogist (2004): 89(5-6): 721-724.
Mineral and/or Locality  
Mindat.org is an outreach project of the Hudson Institute of Mineralogy, a 501(c)(3) not-for-profit organization.
Copyright © mindat.org and the Hudson Institute of Mineralogy 1993-2017, except where stated. Mindat.org relies on the contributions of thousands of members and supporters.
Privacy Policy - Terms & Conditions - Contact Us Current server date and time: September 21, 2017 02:39:43 Page generated: August 21, 2017 14:28:10
Go to top of page