Piccoliite (original) (raw)

A valid IMA mineral species

About PiccoliiteHide

This section is currently hidden. Click the show button to view.

Formula:

NaCaMn3+2(AsO4)2O(OH)

Colour:

Black. It is transparent in thin section although very deep red coloured.

Specific Gravity:

4.084 (Calculated)

Crystal System:

Orthorhombic

Name:

In honour of the mineral collectors Gian Paolo Piccoli (1928–1996) and his son Gian Carlo (b. 1953) for their contribution to the knowledge of the regional mineralogy of Piedmont. It was first recognized on a specimen found in 2007 by Gian Carlo.

Co-Type Localities:

ⓘ Valletta Mine, Vallone della Valletta, Canosio, Cuneo Province, Piedmont, Italy
ⓘ Montaldo Mine (Montaldo di Mondovì Mine), Borgata Oberti, Montaldo di Mondovì, Cuneo Province, Piedmont, Italy

Unique IdentifiersHide

This section is currently hidden. Click the show button to view.

Long-form identifier:

mindat:1:1:51847:1

f9ce2bd8-5f6e-4323-8ef0-50a49595c104

IMA Classification of PiccoliiteHide

This section is currently hidden. Click the show button to view.

Classification of PiccoliiteHide

This section is currently hidden. Click the show button to view.

8.BH.85

8 : PHOSPHATES, ARSENATES, VANADATES
B : Phosphates, etc., with additional anions, without H2O
H : With medium-sized and large cations, (OH,etc.):RO4 = 1:1

Mineral SymbolsHide

This section is currently hidden. Click the show button to view.

As of 2021 there are now IMA–CNMNC approved mineral symbols (abbreviations) for each mineral species, useful for tables and diagrams.

Physical Properties of PiccoliiteHide

This section is currently hidden. Click the show button to view.

Colour:

Black. It is transparent in thin section although very deep red coloured.

Hardness:

VHN5=584 - 657 kg/mm2 - Vickers

Fracture:

Irregular/Uneven

Density:

4.084 g/cm3 (Calculated)

Comment:

Density was not measured. Calculated value is based on empirical data from Montaldo di Mondovì (4.011 for Valletta sample).

Optical Data of PiccoliiteHide

This section is currently hidden. Click the show button to view.

Anisotropism:

Distinct, in shades of grey.

Reflectivity:

Graph shows reflectance levels at different wavelengths (in nm). Top of box is 100%. Peak reflectance is 9.8%.
R1 shown in black, R2 shown in red

Colour in reflected light:

Grey.

Internal Reflections:

Common, in brownish tints.

Comments:

Calculated mean refractive index is 1.878.

Chemistry of PiccoliiteHide

This section is currently hidden. Click the show button to view.

Mindat Formula:

NaCaMn3+2(AsO4)2O(OH)

Chemical AnalysisHide

This section is currently hidden. Click the show button to view.

Empirical formulas:

Crystallography of PiccoliiteHide

This section is currently hidden. Click the show button to view.

Crystal System:

Orthorhombic

Class (H-M):

m m m _(_2/_m_2/_m_2/m ) - Dipyramidal

Cell Parameters:

a = 8.8761(9) Å, b = 7.5190(8) Å, c = 11.689(1) Å

Ratio:

a:b:c = 1.18 : 1 : 1.555

Unit Cell V:

780.12 ų (Calculated from Unit Cell)

Comment:

Data above for Montaldo di Mondovì sample. a = 8.8889, b = 7.5269, c = 11.6795 Å for Valletta sample.

X-Ray Powder DiffractionHide

This section is currently hidden. Click the show button to view.

Powder Diffraction Data:

Comments:

Montaldo Mine, Piedmont, Italy. Data from the type description.

Geological EnvironmentHide

This section is currently hidden. Click the show button to view.

Type Occurrence of PiccoliiteHide

This section is currently hidden. Click the show button to view.

Co-Type Localities:

ⓘ Valletta Mine, Vallone della Valletta, Canosio, Cuneo Province, Piedmont, Italy
ⓘ Montaldo Mine (Montaldo di Mondovì Mine), Borgata Oberti, Montaldo di Mondovì, Cuneo Province, Piedmont, Italy

General Appearance of Type Material:

Aggregates of black anhedral crystals, embedded in the quartz matrix, and rarely as black well-developed prisms.

Place of Conservation of Type Material:

Type material is deposited in the mineralogical collections of the Museo di Storia Naturale Naturale, Università di Pisa,Italy, catalogue number 19906 (holotype), and the Museo Civico Archeologico e di Scienze Naturali “F. Eusebio”, Alba, Italy, catalogue number.

Geological Setting of Type Material:

In Fe–Mn ore hosted in metaquartzites.

Associated Minerals at Type Locality:

Synonyms of PiccoliiteHide

This section is currently hidden. Click the show button to view.

Common AssociatesHide

This section is currently hidden. Click the show button to view.

Associated Minerals Based on Photo Data:

Related Minerals - Strunz-mindat GroupingHide

This section is currently hidden. Click the show button to view.

Fluorescence of PiccoliiteHide

This section is currently hidden. Click the show button to view.

Other InformationHide

This section is currently hidden. Click the show button to view.

Health Risks:

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

Internet Links for PiccoliiteHide

This section is currently hidden. Click the show button to view.

References for PiccoliiteHide

This section is currently hidden. Click the show button to view.

Reference List:

Cámara, F., Biagioni, C., Ciriotti, M.E., Bosi, F., Kolitsch, U., Paar, W.H., Blass, G., Bittarello, E. (2017) Piccoliite, a new mineral of the pilawite group. Joint SIMP-SGI-AIV-SoGeI 2017 Conference "Geosciences: a tool in a changing world", Pisa, Italy, September 3-6, 2017, Abstract book: 120. http://www.socgeol.it/files/download/abstract%20book/abstract_book_pisa_2017_doi.pdf

Cámara, Fernando, Biagioni, Cristian, Ciriotti, Marco E., Bosi, Ferdinando, Kolitsch, Uwe, Paar, Werner H., Hålenius, Ulf, Lepore, Giovanni O., Blass, Günter, Bittarello, Erica (2022) Piccoliite, NaCaMn3+2(AsO4)2O(OH), a new arsenate from the manganese deposits of Montaldo di Mondovì and Valletta, Piedmont, Italy. Mineralogical Magazine, 87 (2) 204-217 doi:10.1180/mgm.2022.129

Localities for PiccoliiteHide

This section is currently hidden. Click the show button to view.

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 section is currently hidden. Click the show button to view.

- This locality has map coordinates listed. - This locality has estimated coordinates. ⓘ - Click for references and 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 (e.g. from pseudomorphs).

All localities listed without proper references should be considered as questionable.