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Khomyakovite Johnsen, O., Gault, R.A., Brice, J.D. & Ercit, T.S. Khomyakovite and manganokhomyakovite, two new members of the eudialyte group from Mont St.-Hilaire, Quebec, Canada. (1999) Canadian Mineralogist 37, 893-899 Khomyakovite, ideally Na12Sr3Ca6Fe3Zr3W (Si25O73)(O,OH,H2O)3(OH,Cl)2 and manganokhomyakovite, ideally Na12Sr3Ca6Mn3Zr3W(Si25O73)(O,OH,H2O)3(OH,Cl)2 are two new members of the eudialyte group from Mont Saint-Hilaire, Quebec. They occur as orange to orange-red, pseudo-octahedral crystals ranging in size from 0.5mm (khomyakovite) to 5mm (manganokhomyakovite). Associated minerals include, for khomyakovite: analcime, annite, calcite, natrolite, pyrite, and titanite, and for manganokhomyakovite: aegirine, albite, analcime, annite, cerussite, galena, kupletskite, microcline, molybdenite, natrolite, pyrite, pyrrhotite, sodalite, sphalerite, titanite, wöhlerite and zircon. Both minerals are transparent to translucent, with a vitreous luster and white streak. They are brittle, with a hardness of 5-6 (Mohs scale). They have no cleavage, no parting and an uneven fracture. They are uniaxial negative, for khomyakovite: w = 1.6279(5) and e = 1.6254(5), and for manganokhomyakovite: w = 1.629(1) and e = 1.626(2). They are trigonal, space group R3m. For khomyakovite: a 14.2959(8), c 30.084(3) Å, V5324.6(7) Å3, and for manganokhomyakovite: a 14.282(3), c 30.12(1) Å, V53206(3) Å3, Z = 3.  Manganokhomyakovite Johnsen, O., Gault, R.A., Brice, J.D. & Ercit, T.S. Khomyakovite and manganokhomyakovite, two new members of the eudialyte group from Mont St.-Hilaire, Quebec, Canada (1999). Canadian Mineralogist 37, 893-899 Khomyakovite, ideally Na12Sr3Ca6Fe3Zr3W (Si25O73)(O,OH,H2O)3(OH,Cl)2 and manganokhomyakovite, ideally Na12Sr3Ca6Mn3Zr3W(Si25O73)(O,OH,H2O)3(OH,Cl)2 are two new members of the eudialyte group from Mont Saint-Hilaire, Quebec. They occur as orange to orange-red, pseudo-octahedral crystals ranging in size from 0.5mm (khomyakovite) to 5mm (manganokhomyakovite). Associated minerals include, for khomyakovite: analcime, annite, calcite, natrolite, pyrite, and titanite, and for manganokhomyakovite: aegirine, albite, analcime, annite, cerussite, galena, kupletskite, microcline, molybdenite, natrolite, pyrite, pyrrhotite, sodalite, sphalerite, titanite, wöhlerite and zircon. Both minerals are transparent to translucent, with a vitreous luster and white streak. They are brittle, with a hardness of 5-6 (Mohs scale). They have no cleavage, no parting and an uneven fracture. They are uniaxial negative, for khomyakovite: w = 1.6279(5) and e = 1.6254(5), and for manganokhomyakovite: w = 1.629(1) and e = 1.626(2). They are trigonal, space group R3m. For khomyakovite: a 14.2959(8), c 30.084(3) Å, V5324.6(7) Å3, and for manganokhomyakovite: a 14.282(3), c 30.12(1) Å, V53206(3) Å3, Z = 3. Oneillite Johnsen, O., Grice, J.D. and Gault, R.A. Oneillite: a new Ca-deficient and REE-rich member of the eudialyte group from Mont Saint-Hilaire, Quebec, Canada. (1999) Canadian Mineralogist 37, 1295-1301 Oneillite, ideally Na15Ca3Mn3Fe3Zr3Nb(Si25O73) (O,OH,H2O)3(OH,Cl)2, is a new member of the eudialyte group from Mont Saint-Hilaire, Quebec. It occurs as yellowish-brown anhedral grains up to 2mm in diameter. Associated minerals include albite, sodalite, pyrite and aegirine. It is transparent to translucent, with a vitreous luster and white streak. It is brittle, with a hardness of 5-6 (Mohs scale). It has no cleavage, no parting, and an uneven fracture. It is uniaxial negative with w = 1.6450(3) and e = 1.6406(3). It is trigonal, space group R3, a 14.192(1) and c 29.983(3) Å, V5230(1) Å3, Z = 3.
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