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Davyne

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Big Photo

Monte Somma, Somma-Vesuvius Complex, Naples Province, Campania, Italy
© Chinellato Matteo

Show Davyne Photos (33)



Formula:
(Na,K)
 
6
Ca
 
2
(Al
 
6
Si
 
6
O
 
24
)(Cl
 
2
,SO
 
4
)
 
2
System:HexagonalColour:Colourless, white
Lustre:VitreousHardness:5½ - 6
Member of:Cancrinite Group
Name:
For Sir Humphrey Davy (1778-1829), English chemist


Cancrinite Group.

Classification of Davyne

IMA status:Valid - first described prior to 1959 (pre-IMA) - "Grandfathered"
Strunz 8th edition ID:8/J.09-20
Nickel-Strunz 10th (pending) edition ID:9.FB.05

9 : SILICATES (Germanates)
F : Tektosilicates without zeolitic H2O
B : Tektosilicates with additional anions
Dana 8th edition ID:76.2.5.5

76 : TECTOSILICATES Al-Si Framework
2 : Al-Si Framework Feldspathoids and related species
Hey's CIM Ref.:17.10.11

17 : Silicates Containing other Anions
10 : Silicates with sulphate, molybdate or tungstate
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Type Occurrence of Davyne

Type Locality:Monte Somma, Somma-Vesuvius Complex, Naples Province, Campania, Italy
Year of Discovery:1825

Occurrences of Davyne

Geological Setting:Volcanic ejecta and leucite rich lavas.

Physical Properties of Davyne

Lustre:Vitreous
Diaphaneity (Transparency):Transparent, Translucent
Colour:Colourless, white
Streak:white
Hardness (Mohs):5½ - 6
Tenacity:Brittle
Cleavage:Perfect
on (10_10)
perfect to indistinct on {0001}
Fracture:Irregular/Uneven, Conchoidal
Density (measured):2.42 - 2.53 g/cm3
Density (calculated):2.50 g/cm3

Crystallography of Davyne

Crystal System:Hexagonal
Class (H-M):6/m - Dipyramidal
Space Group:P63/m
Cell Parameters:a = 12.705(4) Å, c = 5.368(3) Å
Ratio:a:c = 1 : 0.423
Unit Cell Volume:V 750.40 ų (Calculated from Unit Cell)
Z:1
Morphology:Prismatic crystals to 4cm.

Optical Data of Davyne

Type:Uniaxial (+)
RI values: nω = 1.515 - 1.519 nε = 1.519 - 1.522
Maximum Birefringence:δ = 0.004

Chart shows birefringence interference colour range (at 30µm thickness) and does not take into account mineral colouration.
Surface Relief:Low

Chemical Properties of Davyne

Formula:
(Na,K)
 
6
Ca
 
2
(Al
 
6
Si
 
6
O
 
24
)(Cl
 
2
,SO
 
4
)
 
2
Essential elements:Al, Ca, Cl, Na, O, Si
All elements listed in formula:Al, Ca, Cl, K, Na, O, S, Si

Relationship of Davyne to other Species

Member of:Cancrinite Group
Other Members of Group:

- +
Afghanite
(Na,Ca,K)
 
8
(Al
 
6
Si
 
6
O
 
24
)(Cl
 
2
,SO
 
4
,CO
 
3
)
 
3
 · 0.5H
 
2
O
Alloriite
(Na,Ca,K)
 
26
Ca
 
4
(Al
 
6
Si
 
6
O
 
24
)
 
4
(SO
 
4
)
 
6
Cl
 
6
Biachellaite
(Na,Ca,K)
 
8
(Al
 
6
Si
 
6
O
 
24
)(SO
 
4
)
 
2
(OH)
 
0.5
 · H
 
2
O
Bystrite
(Na,K)
 
7
Ca(Al
 
6
Si
 
6
O
 
24
)(S
 
3
)
 
1.5
 · H
 
2
O
Cancrinite
(Na,Ca,☐)
 
8
(Al
 
6
Si
 
6
O
 
24
)(CO
 
3
,SO
 
4
)
 
2
 · 2H
 
2
O
Cancrisilite
Na
 
7
(Al
 
5
Si
 
7
O
 
24
)(CO
 
3
) · 3H
 
2
O
Depmeierite
Na
 
8
(Al
 
6
Si
 
6
O
 
24
)(PO
 
4
,CO
 
3
)
 
1-x
 · 3H
 
2
O (x<0.5)
Franzinite
(Na,K)
 
6
Ca
 
2
(Al
 
6
Si
 
6
O
 
24
)(SO
 
4
)
 
2
 · 0.5H
 
2
O
Giuseppettite
(Na,K,Ca)
 
7-8
(Al
 
6
Si
 
6
O
 
24
)(SO
 
4
,Cl)
 
1-2
Hydroxycancrinite
Na
 
8
(Al
 
6
Si
 
6
O
 
24
)(OH)
 
2
 · 2H
 
2
O
Kircherite
Na
 
5
Ca
 
2
K(Al
 
6
Si
 
6
O
 
24
)(SO
 
4
)
 
2
 · 0.33H
 
2
O
Kyanoxalite
Na
 
7
(Al
 
6-x
Si
 
6+x
O
 
24
)(C
 
2
O
 
4
)
 
0.5+x
 · 5H
 
2
O (0 < x < 0.5)
Liottite
(Na,K)
 
16
Ca
 
8
(Al
 
6
Si
 
6
O
 
24
)
 
3
(SO
 
4
)
 
5
Cl
 
4
Marinellite
(Na,K)
 
42
Ca
 
6
(Al
 
6
Si
 
6
O
 
24
)
 
6
(SO
 
4
)
 
8
Cl
 
2
 · 3H
 
2
O
Microsommite
Na
 
4
K
 
2
Ca
 
2
(Al
 
6
Si
 
6
O
 
24
)(SO
 
4
)Cl
 
2
Pitiglianoite
Na
 
6
K
 
2
(Al
 
6
Si
 
6
O
 
24
)(SO
 
4
) · 2H
 
2
O
Quadridavyne
(Na,K)
 
6
Ca
 
2
(Al
 
6
Si
 
6
O
 
24
)Cl
 
4
Sacrofanite
(Na,K)
 
98
Ca
 
20
(Al
 
6
Si
 
6
O
 
24
)
 
14
(SO
 
4
)
 
26
Cl
 
2
 · 8H
 
2
O
Tounkite
(Na,Ca,K)
 
8
(Al
 
6
Si
 
6
O
 
24
)(SO
 
4
)
 
2
Cl · H
 
2
O
Vishnevite
(Na,K)
 
8
(Al
 
6
Si
 
6
O
 
24
)(SO
 
4
,CO
 
3
) · 2H
 
2
O
Common Associates:
NephelineLeucite
Related Minerals - Nickel-Strunz Grouping):

- +
9.FB.05Afghanite
(Na,Ca,K)
 
8
(Al
 
6
Si
 
6
O
 
24
)(Cl
 
2
,SO
 
4
,CO
 
3
)
 
3
 · 0.5H
 
2
O
9.FB.05Bystrite
(Na,K)
 
7
Ca(Al
 
6
Si
 
6
O
 
24
)(S
 
3
)
 
1.5
 · H
 
2
O
9.FB.05Cancrinite
(Na,Ca,☐)
 
8
(Al
 
6
Si
 
6
O
 
24
)(CO
 
3
,SO
 
4
)
 
2
 · 2H
 
2
O
9.FB.05Cancrisilite
Na
 
7
(Al
 
5
Si
 
7
O
 
24
)(CO
 
3
) · 3H
 
2
O
9.FB.05Franzinite
(Na,K)
 
6
Ca
 
2
(Al
 
6
Si
 
6
O
 
24
)(SO
 
4
)
 
2
 · 0.5H
 
2
O
9.FB.05Giuseppettite
(Na,K,Ca)
 
7-8
(Al
 
6
Si
 
6
O
 
24
)(SO
 
4
,Cl)
 
1-2
9.FB.05Hydroxycancrinite
Na
 
8
(Al
 
6
Si
 
6
O
 
24
)(OH)
 
2
 · 2H
 
2
O
9.FB.05Liottite
(Na,K)
 
16
Ca
 
8
(Al
 
6
Si
 
6
O
 
24
)
 
3
(SO
 
4
)
 
5
Cl
 
4
9.FB.05Microsommite
Na
 
4
K
 
2
Ca
 
2
(Al
 
6
Si
 
6
O
 
24
)(SO
 
4
)Cl
 
2
9.FB.05Pitiglianoite
Na
 
6
K
 
2
(Al
 
6
Si
 
6
O
 
24
)(SO
 
4
) · 2H
 
2
O
9.FB.05Quadridavyne
(Na,K)
 
6
Ca
 
2
(Al
 
6
Si
 
6
O
 
24
)Cl
 
4
9.FB.05Sacrofanite
(Na,K)
 
98
Ca
 
20
(Al
 
6
Si
 
6
O
 
24
)
 
14
(SO
 
4
)
 
26
Cl
 
2
 · 8H
 
2
O
9.FB.05Tounkite
(Na,Ca,K)
 
8
(Al
 
6
Si
 
6
O
 
24
)(SO
 
4
)
 
2
Cl · H
 
2
O
9.FB.05Vishnevite
(Na,K)
 
8
(Al
 
6
Si
 
6
O
 
24
)(SO
 
4
,CO
 
3
) · 2H
 
2
O
9.FB.05Marinellite
(Na,K)
 
42
Ca
 
6
(Al
 
6
Si
 
6
O
 
24
)
 
6
(SO
 
4
)
 
8
Cl
 
2
 · 3H
 
2
O
9.FB.05Farneseite
(Na,Ca,K)
 
56
(Al
 
6
Si
 
6
O
 
24
)
 
7
(SO
 
4
)
 
12
 · 6H
 
2
O
9.FB.05Alloriite
(Na,Ca,K)
 
26
Ca
 
4
(Al
 
6
Si
 
6
O
 
24
)
 
4
(SO
 
4
)
 
6
Cl
 
6
9.FB.05Fantappièite
[Na
 
82.5
Ca
 
33
K
 
16.5
](Si
 
99
Al
 
99
O
 
396
)(SO
 
4
)
 
33
 · 4H
 
2
O
9.FB.05Kyanoxalite
Na
 
7
(Al
 
6-x
Si
 
6+x
O
 
24
)(C
 
2
O
 
4
)
 
0.5+x
 · 5H
 
2
O (0 < x < 0.5)
9.FB.05Balliranoite
(Na,K)
 
6
Ca
 
2
(Si
 
6
Al
 
6
O
 
24
)Cl
 
2
(CO
 
3
)
9.FB.05Carbobystrite
Na
 
8
(Al
 
6
Si
 
6
O
 
24
)(CO
 
3
) · 3.5H
 
2
O
9.FB.05Depmeierite
Na
 
8
(Al
 
6
Si
 
6
O
 
24
)(PO
 
4
,CO
 
3
)
 
1-x
 · 3H
 
2
O (x<0.5)
9.FB.05Kircherite
Na
 
5
Ca
 
2
K(Al
 
6
Si
 
6
O
 
24
)(SO
 
4
)
 
2
 · 0.33H
 
2
O
9.FB.10Bicchulite
Ca
 
2
(Al
 
2
SiO
 
6
)(OH)
 
2
9.FB.10Danalite
Fe
2+
4
(Be
 
3
Si
 
3
O
 
12
)S
9.FB.10Genthelvite
Zn
 
4
(Be
 
3
Si
 
3
O
 
12
)S
9.FB.10Haüyne
(Na,Ca)
 
4-8
(Al
 
6
Si
 
6
(O,S)
 
24
)(SO
 
4
,Cl)
 
1-2
9.FB.10Helvite
Mn
2+
4
(Be
 
3
Si
 
3
O
 
12
)S
9.FB.10Kamaishilite
Ca
 
2
(Al
 
2
SiO
 
6
)(OH)
 
2
9.FB.10Lazurite
(Na,Ca)
 
8
(Al
 
6
Si
 
6
O
 
24
)(S,SO
 
4
,Cl
 
2
)
9.FB.10Nosean
Na
 
8
(Al
 
6
Si
 
6
O
 
24
)(SO
 
4
)
9.FB.10Sodalite
Na
 
8
(Al
 
6
Si
 
6
O
 
24
)Cl
 
2
9.FB.10Tsaregorodtsevite
(N(CH
 
3
)
 
4
)(AlSi
 
5
O
 
12
)
9.FB.10Tugtupite
Na
 
4
(AlBeSi
 
4
O
 
12
)Cl
9.FB.10Helvine
9.FB.15Marialite
Na
 
4
Al
 
3
Si
 
9
O
 
24
Cl
9.FB.15Meionite
Ca
 
4
Al
 
6
Si
 
6
O
 
24
CO
 
3
9.FB.15Silvialite
(Ca,Na)
 
4
[(SO
 
4
,CO
 
3
)|(Al
 
2
Si
 
2
O
 
8
)
 
3
]
Related Minerals - Hey's Index Grouping:

- +
17.10.1Nosean
Na
 
8
(Al
 
6
Si
 
6
O
 
24
)(SO
 
4
)
17.10.2Pitiglianoite
Na
 
6
K
 
2
(Al
 
6
Si
 
6
O
 
24
)(SO
 
4
) · 2H
 
2
O
17.10.3Vishnevite
(Na,K)
 
8
(Al
 
6
Si
 
6
O
 
24
)(SO
 
4
,CO
 
3
) · 2H
 
2
O
17.10.4Haüyne
(Na,Ca)
 
4-8
(Al
 
6
Si
 
6
(O,S)
 
24
)(SO
 
4
,Cl)
 
1-2
17.10.5Liottite
(Na,K)
 
16
Ca
 
8
(Al
 
6
Si
 
6
O
 
24
)
 
3
(SO
 
4
)
 
5
Cl
 
4
17.10.6Latiumite
K
 
2
Ca
 
6
(Si,Al)
 
11
O
 
25
(SO
 
4
,CO
 
3
)
17.10.7Tuscanite
(K(Ca,Na)
 
6
(Si,Al)
 
10
O
 
22
[SO
 
4
,CO
 
3
,(OH)
 
2
] · H
 
2
O
17.10.8Microsommite
Na
 
4
K
 
2
Ca
 
2
(Al
 
6
Si
 
6
O
 
24
)(SO
 
4
)Cl
 
2
17.10.9Delhayelite
(Na,K)
 
10
Ca
 
5
Al
 
6
Si
 
32
O
 
80
(Cl
 
2
,F
 
2
,SO
 
4
)
 
3
 · 18H
 
2
O
17.10.10Hydrodelhayelite
KCa
 
2
AlSi
 
7
O
 
17
(OH)
 
2
 · 6H
 
2
O
17.10.12Afghanite
(Na,Ca,K)
 
8
(Al
 
6
Si
 
6
O
 
24
)(Cl
 
2
,SO
 
4
,CO
 
3
)
 
3
 · 0.5H
 
2
O
17.10.13Franzinite
(Na,K)
 
6
Ca
 
2
(Al
 
6
Si
 
6
O
 
24
)(SO
 
4
)
 
2
 · 0.5H
 
2
O
17.10.14Giuseppettite
(Na,K,Ca)
 
7-8
(Al
 
6
Si
 
6
O
 
24
)(SO
 
4
,Cl)
 
1-2
17.10.15Sacrofanite
(Na,K)
 
98
Ca
 
20
(Al
 
6
Si
 
6
O
 
24
)
 
14
(SO
 
4
)
 
26
Cl
 
2
 · 8H
 
2
O
17.10.16Chessexite
(Na,K)
 
4
Ca
 
2
(Mg,Zn)
 
3
Al
 
8
(SO
 
4
)
 
10
(SiO
 
4
)
 
2
 · 40H
 
2
O
17.10.17Innelite
Na
 
2
CaBa
 
4
Ti
 
3
(Si
 
2
O
 
7
)
 
2
(SO
 
4
)
 
2
O
 
4
17.10.18Thaumasite
Ca
 
3
(SO
 
4
)[Si(OH)
 
6
](CO
 
3
) · 12H
 
2
O
17.10.19Ellestadite
17.10.20Ellestadite-(Cl)
Ca
 
10
(SiO
 
4
)
 
3
(SO
 
4
)
 
3
Cl
 
2
17.10.21Hydroxylellestadite
Ca
 
5
(SiO
 
4
)
 
1.5
(SO
 
4
)
 
1.5
(OH)
17.10.22Fluorellestadite
Ca
 
5
(SiO
 
4
)
 
1.5
(SO
 
4
)
 
1.5
F
17.10.23Mattheddleite
Pb
 
5
(SiO
 
4
)
 
1.5
(SO
 
4
)
 
1.5
(Cl,OH)
17.10.24Queitite
Pb
 
4
Zn
 
2
(SO
 
4
)(SiO
 
4
)(Si
 
2
O
 
7
)
17.10.25Roeblingite
Pb
 
2
Ca
 
6
Mn
2+
 
(Si
 
3
O
 
9
)
 
2
(SO
 
4
)
 
2
(OH)
 
2
 · 4H
 
2
O
17.10.26Yoshimuraite
Ba
 
2
Mn
 
2
Ti(Si
 
2
O
 
7
)(PO
 
4
)O(OH)
17.10.27Kegelite
Pb
 
8
Al
 
4
(Si
 
8
O
 
20
)(SO
 
4
)
 
2
(CO
 
3
)
 
4
(OH)
 
8
17.10.28Wenkite
(Ba,K)
 
4
(Ca,Na)
 
6
[(SO
 
4
)
 
3
|(Si,Al)
 
20
O
 
39
(OH)
 
2
] · 0.5H
 
2
O
17.10.29Macquartite
Pb
 
3
Cu(CrO
 
4
)(SiO
 
3
)(OH)
 
4
 · 2H
 
2
O
17.10.30Welinite
Mn
2+
6
(W
6+
 
,Mg)
 
2
(SiO
 
4
)
 
2
(O,OH)
 
6

Other Names for Davyne

Other Languages:
German:Davyn
Russian:Давин
Varieties:
Acarbodavyne

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 Davyne

Reference List:

- +
Monticelli, T., Covelli, N. (1825): Prodromo della Mineralogica Vesuviana, Napoli.

Haidinger, W. (1827): Über den Davyn, eine neue Mineralspecies, Annalen der Physik und Chemie, Vol. 87/F2-11, 470-474.

Bonaccorsi E., Merlino S., Pasero M.(1990): Davyne: its structural relationships with cancrinite and vishnevite. Neues Jahrbuch für Mineralogie, Monatshefte, H. 3, 97-112.

Canadian Mineralogist (1990): 28: 341-349.

Internet Links for Davyne

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    • Localities for Davyne

    The 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.
    Hide Locality List
    (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.
    Egypt
     
    • Red Sea
    		Bonaccorsi E., Merlino S., Pasero M.(1991): Davyne from Zabargad (St. John's) Island: peculiar chemical and structural features. Acta Vulcanol., 2, 55-63.
    Germany
     
    • Rhineland-Palatinate
      • Eifel Mts
        • Andernach
          • Eich
    		Hentschel, G., Die Mineralien der Eifelvulkane, Weise Verlag München, 1983
        • Laach lake volcanic complex
          • Kruft
    		Brauns, R. ; Uhlig, J., Cancrinit- und Nephelin-führende Auswürflinge aus dem Laacher See Gebiet, N.Jb. Mineral.Geol.Paläonolog., Beil. Band 56, Abt. A, 468-498, 1913
          • Mendig
            • Niedermendig
    		Brauns, R. ; Uhlig, J., Cancrinit- und Nephelin-führende Auswürflinge aus dem Laacher See Gebiet, N.Jb. Mineral.Geol.Paläonolog., Beil. Band 56, Abt. A, 468-498, 1913
    Brauns, R. ; Uhlig, J., Cancrinit- und Nephelin-führende Auswürflinge aus dem Laacher See Gebiet, N.Jb. Mineral.Geol.Paläonolog., Beil. Band 56, Abt. A, 468-498, 1913)
              • Wingertsberg Mt.
    		Brauns, R. ; Uhlig, J., Cancrinit- und Nephelin-führende Auswürflinge aus dem Laacher See Gebiet, N.Jb. Mineral.Geol.Paläonolog., Beil. Band 56, Abt. A, 468-498, 1913
          • Niederzissen
            • Glees
    		Brauns, R. ; Uhlig, J., Cancrinit- und Nephelin-führende Auswürflinge aus dem Laacher See Gebiet, N.Jb. Mineral.Geol.Paläonolog., Beil. Band 56, Abt. A, 468-498, 1913
        • Mayen
          • Ettringen
            • Bellerberg volcano
    		[Blass, G., Graf, H.W., Interessante Neuigkeiten über Cancrinit, Fluorit und Fuchsit aus der Vulkaneifel, Mineralien-Welt 12/1, 26-29, 2001] [Lapis, 15 (5), 9-36]
        • Niederzissen
          • Brenk
    		Blass, G., Graf , HW., Interessante Neuigkeiten über Cancrinit, Fluorit und Fuchsit aus der Vulkaneifel, MW 1/2001
          • Burgbrohl
    		Blass, G., Graf , HW., Neufunde von bekannten Fundorten (VI), MW 6/1992
          • Hannebach
    		Hentschel, G., Die Mineralien der Eifelvulkane, Weise Verlag München, 1983
    Italy
     
    • Campania
      • Naples Province
        • Somma-Vesuvius Complex
    		NJMM (1990) (3), 97
            • Ercolano
              • San Vito
            • Pollena - Trocchia area
    		Carati M., 1982. Guida alla mineralogia vesuviana. Guide Calderini, Bologna.
    M. Carati - Guida alla mineralogia vesuviana - Calderini, Bologna, 1982
    [BINON J., BONACCORSI E., BERNHARDT H.J., FRANSOLET A. M. (2004) - The mineralogical status of "cavolinite" from Vesuvius, Italy, and crystallochemical data on the davyne subgroup. Eur. J. Mineral., 16 (3), 511-520] [Russo, M., Punzo, I. (2004): I minerali del Somma-Vesuvio, AMI]
            • Terzigno
    		Luigi Chiappino data
    • Latium
      • Viterbo Province
    		Stoppani, F.S., Curti, E. (1982): I Minerali del Lazio. Ed. Olimpia, Firenze, 154-158
        • Vico Lake
    		No reference listed
    • Tuscany
      • Grosseto Province
        • Pitigliano
    		Liotti L., 1991. I minerali dei vulcani laziali a Pitigliano (Grosseto). Riv. Mineral. Ital., 15 (3): 121-139.
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