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MINERAL CLASSIFICATION / SYSTEMATIK der MINERALE based on E.H. Nickel & M.C. Nichols (2009), H. Strunz & E.H. Nickel (2001), revised by Thomas Witzke (2023) 6. BORATES 6.B: Soroborates | ||||||||||||||||
6.BA. Soro-diborates with double triangles B2(O,OH)5, (2Δ) | ||||||||||||||||
6.BA.005. Suanite | ||||||||||||||||
Suanite | Mg2(B2O5) | tric., P1 | A | |||||||||||||
6.BA.010. Shimazakiite | ||||||||||||||||
Shimazakiite | Ca2(B2O5) | mon., P21/c | IMA 2010-085a | |||||||||||||
Shimazakiite polytypes: Shimazakiite-4M (mon., P21/c), Shimazakiite-4O (orth., P212121). | ||||||||||||||||
6.BA.015. Kurchatovite group | ||||||||||||||||
Kurchatovite | CaMg(B2O5) | orth., Pca21 | IMA 1965-034 | |||||||||||||
Clinokurchatovite | CaMg(B2O5) | mon., P21/c | IMA 1982-017 | |||||||||||||
6.BA.020. Szaibelyite group | ||||||||||||||||
Szaibelyite | Mg2(B2O4OH)(OH) | mon., P21/a | FOTO | A | ||||||||||||
Sussexite | Mn2(B2O4OH)(OH) | mon., P21/a | G | |||||||||||||
6.BA.025. Wiserite | ||||||||||||||||
Wiserite | Mn14(B2O5)4(OH)8·(Si,Mg)(O,OH)4Cl | tetr., P4/n | G | |||||||||||||
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6.BB. Soro-diborates with triangle + tetrahedron, B2O4(OH)2, (Δ□) | ||||||||||||||||
6.BB.005. Krasnoshteinite | ||||||||||||||||
Krasnoshteinite | Al8[B2O4(OH)2](OH)16Cl4·7H2O | mon., P21 | IMA 2018-077 | |||||||||||||
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6.BC. Soro-diborates with double tetrahedra B2O(OH)6, (2□) | ||||||||||||||||
6.BC.005. Pinnoite | ||||||||||||||||
Pinnoite | Mg(B2O(OH)6) | tetr., P42 | FOTO | G | ||||||||||||
6.BC.010. Pentahydroborite | ||||||||||||||||
Pentahydroborite | Ca(B2O(OH)6)·2H2O | tric, P1 | A | |||||||||||||
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G = Grandfathered minerals: original description preceded the establishment of the CNMNC in 1959, and generally regarded as a valid species A or IMA No. = Minerals approved by the CNMNC Rd = Redefinition of the mineral approved by the CNMNC Rn = Renamed with approval by the CNMNC Q = Questionable mineral Classification principles: The classification is based on the linkage of borate triangles (BO3), symbol Δ, and borate tetrahedra (BO4), symbol □, to form fundamental building blocks (FBB) (see in Grice et al., 1999). According to the polymerization of the borate groups the subdivision is made now into Neso-, Soro-, Cyclo-, Ino-, Phyllo- and Tecto-borates, adapted from the well-known subdivision of the Silicates class and following the recommendation in Mills et al. (2009) on the standardisation of mineral group hierarchies. Soroborates are minerals with isolated clusters of connected borate groups. This definition would be fulfilled also by Cycloborates with isolated clusters of borate groups in ring-shaped arrangement. In fact, these ring-shaped arrangements are classified in Grice et al. (1999) as Soroborates, and Cycloborates are not mentioned. In the classification here the Cycloborates are treated as a separate subclass to adapt the classification of the Silicates (Mills et al., 2009). Therefore, only minerals with clusters of connected borate groups with a linear shape are classified here as Soroborates. In natural minerals only linear arrangements of two connected borate groups exist, larger linear units with three or more connected borate groups are not known up to now. The further subdivision of the subclass "6.B: Soroborates" is made according to the type of the connected borate groups into 6.BA. Soro-diborates with double triangles B2(O,OH)5, (2Δ); 6.BB. Soro-diborates with triangle + tetrahedron, B2O4(OH)2, (Δ□); 6.BC. Soro-diborates with double tetrahedra B2O(OH)6, (2□). Further classification: 6.BA. Soro-diborates with double triangles B2(O,OH)5, (2Δ): Without other anions or water; with other anions or water. 6.BB. Soro-diborates with triangle + tetrahedron, B2O4(OH)2, (Δ□): Only one mineral. 6.BC. Soro-diborates with double tetrahedra B2O(OH)6, (2□): Without other anions or water; with other anions or water. Reference: Grice, J.D.; Burns, P.C. & Hawthorne, F.C. (1999): Borate Minerals. II. A hierarchy of structures based upon the borate fundamental building block. Can. Min. 37, 731-762. Mills, S.J.; Hatert, F.; Nickel, E. & Ferraris, G. (2009): The standardisation of mineral group hierarchies: application to recent nomenclature proposals. Eur. J. Mineral. 21, 1073-1080. To distinguish from classical Strunz numbering, on hierarchical "group" level, a numbering with 3 digits is used, like "6.BA.005. Suanite", instead of 2 digits (like "6.BA.05.") in the Strunz system. © Thomas Witzke (2023) |
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