IMA 2009-058 = dalnegroite
- Marco E. Ciriotti
- Messaggi: 31645
- Iscritto il: ven 25 giu, 2004 11:31
- Località: via San Pietro, 55 I-10073 Devesi/Cirié TO - Italy
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IMA 2009-058 = dalnegroite
Il nome della nuova specie di Lengenbach (IMA 2009-058) è dalnegroite. La descrizione-tipo è di prossima pubblicazione sul Mineralogical Magazine.
Referenza:
• Nestola, F., Guastoni, A., Bindi, L., Secco, L. (2009): Dalnegroite, Tl5-xPb2x(As,Sb)21-xS34, a new thallium sulphosalt from Lengenbach quarry, Binntal, Switzerland. Mineralogical Magazine, 73, (in press).
Abstract:
Dalnegroite, ideally Tl4Pb2(As12Sb8)?20S34, is a new mineral from Lengenbach, Binntal, Switzerland. It occurs as anhedral to subhedral grains up to 200 ?m across, closely associated with realgar, pyrite, Sb-rich seligmanite in a gangue of dolomite. Dalnegroite 0is opaque with a submetallic lustre and shows a brownish-red streak. It is brittle; the Vickers hardness (VHN25) is 87 kg mm–2 (range: 69–101) (Mohs hardness ~3–3 1/2). In reflected light, dalnegroite is highly bireflectant and weakly pleochroic, from white to a slightly greenish-grey. In cross-polarized light, it is highly anisotropic with bluish to green rotation tints and red internal reflections.
According to chemical and X-ray diffraction data, dalnegroite appears to be isotypic with chabournéite, Tl5–xPb2x(Sb,As)21–xS34. It is triclinic, probable space group P1, with a = 16.217(7) Å, b = 42.544(9) Å, c = 8.557(4) Å, ? = 95.72(4)°, ? = 90.25(4)°, ? = 96.78(4)°, V = 5832(4) Å3, Z = 4.
The nine strongest powder-diffraction lines [d (Å) (I/I0,) (hkl)] are: 3.927 100 (-2 10 0); 3.775 (45) (2-22); 3.685 (45) (-460); 3.620 (50) (440); 3.124 (50) (-2-82); 2.929 (60) (4-22); 2.850 (70) (-442); 2.579 (45) (0 -14 2); 2.097 (60) (024). The mean of 11 electron microprobe analyses gave elemental concentrations as follows: Pb 10.1(1) wt.% , Tl 20.4(1), Sb 23.0(1), As 21.3(8), S 26.2(8), totalling 100.6 wt.%, corresponding to Tl4.15Pb2.03(As11.86Sb8.20)S34. The new mineral is named for Alberto Dal Negro, Professor in Mineralogy and Crystallography at the University of Padova since 1976.
Referenza:
• Nestola, F., Guastoni, A., Bindi, L., Secco, L. (2009): Dalnegroite, Tl5-xPb2x(As,Sb)21-xS34, a new thallium sulphosalt from Lengenbach quarry, Binntal, Switzerland. Mineralogical Magazine, 73, (in press).
Abstract:
Dalnegroite, ideally Tl4Pb2(As12Sb8)?20S34, is a new mineral from Lengenbach, Binntal, Switzerland. It occurs as anhedral to subhedral grains up to 200 ?m across, closely associated with realgar, pyrite, Sb-rich seligmanite in a gangue of dolomite. Dalnegroite 0is opaque with a submetallic lustre and shows a brownish-red streak. It is brittle; the Vickers hardness (VHN25) is 87 kg mm–2 (range: 69–101) (Mohs hardness ~3–3 1/2). In reflected light, dalnegroite is highly bireflectant and weakly pleochroic, from white to a slightly greenish-grey. In cross-polarized light, it is highly anisotropic with bluish to green rotation tints and red internal reflections.
According to chemical and X-ray diffraction data, dalnegroite appears to be isotypic with chabournéite, Tl5–xPb2x(Sb,As)21–xS34. It is triclinic, probable space group P1, with a = 16.217(7) Å, b = 42.544(9) Å, c = 8.557(4) Å, ? = 95.72(4)°, ? = 90.25(4)°, ? = 96.78(4)°, V = 5832(4) Å3, Z = 4.
The nine strongest powder-diffraction lines [d (Å) (I/I0,) (hkl)] are: 3.927 100 (-2 10 0); 3.775 (45) (2-22); 3.685 (45) (-460); 3.620 (50) (440); 3.124 (50) (-2-82); 2.929 (60) (4-22); 2.850 (70) (-442); 2.579 (45) (0 -14 2); 2.097 (60) (024). The mean of 11 electron microprobe analyses gave elemental concentrations as follows: Pb 10.1(1) wt.% , Tl 20.4(1), Sb 23.0(1), As 21.3(8), S 26.2(8), totalling 100.6 wt.%, corresponding to Tl4.15Pb2.03(As11.86Sb8.20)S34. The new mineral is named for Alberto Dal Negro, Professor in Mineralogy and Crystallography at the University of Padova since 1976.
Marco E. Ciriotti
«Things are interesting only in so far as they relate themselves to other things»
«Things are interesting only in so far as they relate themselves to other things»
- Marco E. Ciriotti
- Messaggi: 31645
- Iscritto il: ven 25 giu, 2004 11:31
- Località: via San Pietro, 55 I-10073 Devesi/Cirié TO - Italy
- Contatta:
Re: IMA 2009-058 = dalnegroite
La formula qui proposta per la chabournéite, con Z = 4, pare più in linea di quella presente sulla lista IMA CNMNC.dalnegroite appears to be isotypic with chabournéite, Tl5–xPb2x(Sb,As)21–xS34
Un nuovo gruppo [chabournéite group] va quindi a formarsi ---> 2. H C. 05 e:
A Chabournéite Tl5-xPb2x(Sb,As)21-xS34 (x = ~1) tric P1 16.320 42.636 8.543 83.98 89.06 83.20 4
A Dalnegroite Tl5-xPb2x(As,Sb)21-xS34 (x = ~1) tric P1 16.217 42.544 8.557 95.72 90.25 96.78 4
Marco E. Ciriotti
«Things are interesting only in so far as they relate themselves to other things»
«Things are interesting only in so far as they relate themselves to other things»
- Marco E. Ciriotti
- Messaggi: 31645
- Iscritto il: ven 25 giu, 2004 11:31
- Località: via San Pietro, 55 I-10073 Devesi/Cirié TO - Italy
- Contatta:
Re: IMA 2009-058 = dalnegroite
Congratulazioni vivissime al team che ha caratterizzato l'interessante nuova specie (i minerali di tallio sono sempre intriganti!).
Dalnegroite è la 30° nuova specie, con località-tipo non nazionale, dedicata a personaggi o istituzioni italiane.
La referenza completa è la seguente:
Referenza:
• Nestola, F., Guastoni, A., Bindi, L., Secco, L. (2009): Dalnegroite, Tl5-xPb2x(As,Sb)21-xS34, a new thallium sulphosalt from Lengenbach quarry, Binntal, Switzerland. Mineralogical Magazine, 73, 1027-1032.
Dalnegroite è la 30° nuova specie, con località-tipo non nazionale, dedicata a personaggi o istituzioni italiane.
La referenza completa è la seguente:
Referenza:
• Nestola, F., Guastoni, A., Bindi, L., Secco, L. (2009): Dalnegroite, Tl5-xPb2x(As,Sb)21-xS34, a new thallium sulphosalt from Lengenbach quarry, Binntal, Switzerland. Mineralogical Magazine, 73, 1027-1032.
Marco E. Ciriotti
«Things are interesting only in so far as they relate themselves to other things»
«Things are interesting only in so far as they relate themselves to other things»
-
- Messaggi: 15
- Iscritto il: mer 20 gen, 2010 0:31
Re: IMA 2009-058 = dalnegroite
Salve a tutti,
approfitto della mia nuova iscrizione al forum per una precisazione in merito alla descrizione della dalnegroite su Mineralogical Magazine, 73, pp. 1027-1032. Nella foto SEM di pag. 1028, come pure nella descrizione della paragenesi del minerale, è indicata erroneamente la presenza di jordanite. Il minerale in questione è in realtà sartorite, la jordanite non è presente in alcuna parte del campione dove ho scoperto la dalnegroite, nè è presente sugli unici altri due esemplari dove ho osservato la presenza di questo rarissimo minerale. Luca De Battisti
approfitto della mia nuova iscrizione al forum per una precisazione in merito alla descrizione della dalnegroite su Mineralogical Magazine, 73, pp. 1027-1032. Nella foto SEM di pag. 1028, come pure nella descrizione della paragenesi del minerale, è indicata erroneamente la presenza di jordanite. Il minerale in questione è in realtà sartorite, la jordanite non è presente in alcuna parte del campione dove ho scoperto la dalnegroite, nè è presente sugli unici altri due esemplari dove ho osservato la presenza di questo rarissimo minerale. Luca De Battisti
- Marco E. Ciriotti
- Messaggi: 31645
- Iscritto il: ven 25 giu, 2004 11:31
- Località: via San Pietro, 55 I-10073 Devesi/Cirié TO - Italy
- Contatta:
Re: IMA 2009-058 = dalnegroite
Grazie molte, Luca, della debita precisazione.
Un'altra piccola imprecisione riguarda il tuo nome indicato come "Luca Debattisti" in luogo di "Luca De Battisti".
Complimenti vivissimi, Luca, per i numerosi interessantissimi ritrovamenti da te effettuati a Lengenbach, tra cui questa nuova rara specie.
Un'altra piccola imprecisione riguarda il tuo nome indicato come "Luca Debattisti" in luogo di "Luca De Battisti".
Complimenti vivissimi, Luca, per i numerosi interessantissimi ritrovamenti da te effettuati a Lengenbach, tra cui questa nuova rara specie.
Marco E. Ciriotti
«Things are interesting only in so far as they relate themselves to other things»
«Things are interesting only in so far as they relate themselves to other things»
- Graziano Del Core
- Messaggi: 183
- Iscritto il: mar 16 dic, 2008 15:30
- Località: Torino
Re: IMA 2009-058 = dalnegroite
Ciao Luca,
mi fa veramente piacere che tu abbia scoperto il nuovo minerale contenente Tl.
D'altronde leggendo la località-tipo balena subito alla mia mente la tua grande conoscenza sui minerali di Lengenbach!
Saluti e a presto incontrarci.
Graziano
mi fa veramente piacere che tu abbia scoperto il nuovo minerale contenente Tl.
D'altronde leggendo la località-tipo balena subito alla mia mente la tua grande conoscenza sui minerali di Lengenbach!
Saluti e a presto incontrarci.
Graziano
Graziano Del Core (Socio A.P.M.P.)
Aliena vitia in oculis habemus, a tergo nostra sunt (Seneca)
Aliena vitia in oculis habemus, a tergo nostra sunt (Seneca)
- domenico
- Messaggi: 5648
- Iscritto il: gio 30 set, 2004 11:40
- Località: Garbagnate Milanese (Mi)
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Re: IMA 2009-058 = dalnegroite
Grazie Luca.Graziano Del Core ha scritto:Ciao Luca,
mi fa veramente piacere che tu abbia scoperto il nuovo minerale contenente Tl.
D'altronde leggendo la località-tipo balena subito alla mia mente la tua grande conoscenza sui minerali di Lengenbach!
Saluti e a presto incontrarci.
Graziano
Ottima presentazione come da te promesso... del resto, e complimenti per questa e tutte le cose grandiose della Binntal...
La collezione dei minerali è un divertimento se qualcuno non ci crede può collezionare le farfalle
Domenico Preite Marzo 2008
http://www.mindat.org/user-6983.html#2
Domenico Preite Marzo 2008
http://www.mindat.org/user-6983.html#2
- Marco E. Ciriotti
- Messaggi: 31645
- Iscritto il: ven 25 giu, 2004 11:31
- Località: via San Pietro, 55 I-10073 Devesi/Cirié TO - Italy
- Contatta:
Re: IMA 2009-058 = dalnegroite
Di prossima pubblicazione sul Mineralogical Magazine la risoluzione della struttura della dalnegroite.
Referenza:
▪ Bindi, L., Nestola, F., Guastoni, A., Secco, L. (2010): The crystal structure of dalnegroite, Tl5–xPb2x(As,Sb)21–xS34: a masterpiece of structural complexity. Mineralogical Magazine, 74, (in press).
Abstract:
The crystal structure of the rare mineral dalnegroite, Tl5–xPb2x(As,Sb)21–xS34 with x ≈ 1, was determined for a crystal from Lengenbach, Binn Valley, Switzerland. The structure is triclinic, space group P1, with a = 16.218(3), b = 42.546(7), c = 8.558(1) Å, α = 95.70(4), β = 90.18(3), γ = 96.38(4)°, V = 5838.9(9) Å3, Z = 4. Refinement of an isotropic model led to an R1 index of 0.0536 for 22226 observed reflections and 980 parameters, and R1 = 0.0590 for all 25266 independent reflections. Although dalnegroite cannot be considered a layered compound, its structure can be usefully described as a regular alternation of two kinds of layers stacked along the b axis, with four layers in the unit cell: (1) a layer 7.8 Å thick, at y ≈ 0.15 and 0.65, can be considered as derived from the SnS archetype; (2) a layer 13.6 Å thick, at y ≈ 0.35 and 0.85, derived from the PbS archetype. Different chemical compositions, such as Tl:Pb and Sb:As ratios, for different samples belonging to the chabournéite-dalnegroite family could play a central role in controlling different degrees of order, leading to different superstructures.
Referenza:
▪ Bindi, L., Nestola, F., Guastoni, A., Secco, L. (2010): The crystal structure of dalnegroite, Tl5–xPb2x(As,Sb)21–xS34: a masterpiece of structural complexity. Mineralogical Magazine, 74, (in press).
Abstract:
The crystal structure of the rare mineral dalnegroite, Tl5–xPb2x(As,Sb)21–xS34 with x ≈ 1, was determined for a crystal from Lengenbach, Binn Valley, Switzerland. The structure is triclinic, space group P1, with a = 16.218(3), b = 42.546(7), c = 8.558(1) Å, α = 95.70(4), β = 90.18(3), γ = 96.38(4)°, V = 5838.9(9) Å3, Z = 4. Refinement of an isotropic model led to an R1 index of 0.0536 for 22226 observed reflections and 980 parameters, and R1 = 0.0590 for all 25266 independent reflections. Although dalnegroite cannot be considered a layered compound, its structure can be usefully described as a regular alternation of two kinds of layers stacked along the b axis, with four layers in the unit cell: (1) a layer 7.8 Å thick, at y ≈ 0.15 and 0.65, can be considered as derived from the SnS archetype; (2) a layer 13.6 Å thick, at y ≈ 0.35 and 0.85, derived from the PbS archetype. Different chemical compositions, such as Tl:Pb and Sb:As ratios, for different samples belonging to the chabournéite-dalnegroite family could play a central role in controlling different degrees of order, leading to different superstructures.
Marco E. Ciriotti
«Things are interesting only in so far as they relate themselves to other things»
«Things are interesting only in so far as they relate themselves to other things»
- Marco E. Ciriotti
- Messaggi: 31645
- Iscritto il: ven 25 giu, 2004 11:31
- Località: via San Pietro, 55 I-10073 Devesi/Cirié TO - Italy
- Contatta:
Re: IMA 2009-058 = dalnegroite
Referenza:
▪ Bindi, L., Nestola, F., Guastoni, A., Secco, L. (2010): The crystal structure of dalnegroite, Tl5–xPb2x(As,Sb)21–xS34: a masterpiece of structural complexity. Mineralogical Magazine, 74, 999-1012.
Abstract:
The crystal structure of the rare mineral dalnegroite, Tl5–xPb2x(As,Sb)21–xS34 with x ≈ 1, was determined for a crystal from Lengenbach, Binn Valley, Switzerland. The structure is triclinic, space group P1, with a = 16.218(3), b = 42.546(7), c = 8.558(1) Å, α = 95.70(4), β = 90.18(3), γ = 96.38(4)°, V = 5838.9(9) Å3, Z = 4. Refinement of an isotropic model led to an R1 index of 0.0536 for 22226 observed reflections and 980 parameters, and R1 = 0.0590 for all 25266 independent reflections. Although dalnegroite cannot be considered a layered compound, its structure can be usefully described as a regular alternation of two kinds of layers stacked along the b axis, with four layers in the unit cell: (1) a layer 7.8 Å thick, at y ≈ 0.15 and 0.65, can be considered as derived from the SnS archetype; (2) a layer 13.6 Å thick, at y ≈ 0.35 and 0.85, derived from the PbS archetype. Different chemical compositions, such as Tl:Pb and Sb:As ratios, for different samples belonging to the chabournéite-dalnegroite family could play a central role in controlling different degrees of order, leading to different superstructures.
▪ Bindi, L., Nestola, F., Guastoni, A., Secco, L. (2010): The crystal structure of dalnegroite, Tl5–xPb2x(As,Sb)21–xS34: a masterpiece of structural complexity. Mineralogical Magazine, 74, 999-1012.
Abstract:
The crystal structure of the rare mineral dalnegroite, Tl5–xPb2x(As,Sb)21–xS34 with x ≈ 1, was determined for a crystal from Lengenbach, Binn Valley, Switzerland. The structure is triclinic, space group P1, with a = 16.218(3), b = 42.546(7), c = 8.558(1) Å, α = 95.70(4), β = 90.18(3), γ = 96.38(4)°, V = 5838.9(9) Å3, Z = 4. Refinement of an isotropic model led to an R1 index of 0.0536 for 22226 observed reflections and 980 parameters, and R1 = 0.0590 for all 25266 independent reflections. Although dalnegroite cannot be considered a layered compound, its structure can be usefully described as a regular alternation of two kinds of layers stacked along the b axis, with four layers in the unit cell: (1) a layer 7.8 Å thick, at y ≈ 0.15 and 0.65, can be considered as derived from the SnS archetype; (2) a layer 13.6 Å thick, at y ≈ 0.35 and 0.85, derived from the PbS archetype. Different chemical compositions, such as Tl:Pb and Sb:As ratios, for different samples belonging to the chabournéite-dalnegroite family could play a central role in controlling different degrees of order, leading to different superstructures.
Marco E. Ciriotti
«Things are interesting only in so far as they relate themselves to other things»
«Things are interesting only in so far as they relate themselves to other things»
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