New Minerals from Inclusions in Corundum Xenocrysts from Mt. Carmel, Israel: Magnéliite, Ziroite, Sassite, Mizraite-(Ce) and Yeite.

Our nanomineralogical investigation of melt inclusions in corundum xenocrysts from the Mt. Carmel area, Israel has revealed seven IMA-approved new minerals since 2021. We report here four new oxide minerals and one new alloy mineral. Magnéliite (Ti 3+ 2 Ti 4+ 2 O 7 ; IMA 2021-111) occurs as subhedral crystals, ~4 μm in size, with alabandite, zirconolite, Ti,Al,Zr-oxide, and hibonite in corundum Grain 767-1. Magnéliite has an empirical formula (Ti 3+ 1.66 Al 0.13 Ti 4+ 0.15 Mg 0.10 Ca 0.01 Sc 0.01 ) Σ2.06 (Ti 4+ 1.93 Zr 0.08 ) Σ2.01 O 7 and the triclinic P 1¯ Ti 4 O 7 -type structure with the cell parameters: a = 5.60(1) Å, b = 7.13(1) Å, c = 12.47(1) Å, α = 95.1(1)°, β = 95.2(1)°, γ = 108.7(1)°, V = 466(2) Å 3 , Z = 4. Ziroite (ZrO 2 ; IMA 2022-013) occurs as irregular crystals, ~1-4 μm in size, with baddeleyite, hibonite, and Ti,Al,Zr-oxide in corundum Grain 479-1a. Ziroite has an empirical formula (Zr 0.72 Ti 4+ 0.26 Mg 0.02 Al 0.02 Hf 0.01 ) Σ1.03 O 2 and the tetragonal P 4 2 / nmc zirconia(HT)-type structure with the cell parameters: a = 3.60(1) Å, c = 5.18(1) Å, V = 67.1(3) Å 3 , Z = 2. Sassite (Ti 3+ 2 Ti 4+ O 5 ; IMA 2022-014) occurs as subhedral-euhedral crystals, ~4-16 μm in size, with Ti,Al,Zr-oxide, mullite, osbornite, baddeleyite, alabandite, and glass in corundum Grain 1125C1. Sassite has an empirical formula (Ti 3+ 1.35 Al 0.49 Ti 4+ 0.08 Mg 0.07 ) Σ1.99 (Ti 4+ 0.93 Zr 0.06 Si 0.01 ) Σ1.00 O 5 and the orthorhombic Cmcm pseudobrookite-type structure with the cell parameters: a = 3.80(1) Å, b = 9.85(1) Å, c = 9.99(1) Å, V = 374(1) Å 3 , Z = 4. Mizraite-(Ce) (Ce(Al 11 Mg)O 19 ; IMA 2022-027) occurs as euhedral crystals, <1-14 μm in size, with Ce-silicate, Ti-sulfide, Ti,Al,Zr-oxide, ziroite, and thorianite in corundum Grain 198-8. Mizraite-(Ce) has an empirical formula (Ce 0.76 Ca 0.10 La 0.07 Nd 0.01 ) Σ0.94 (Al 10.43 Mg 0.84 Ti 3+ 0.60 Si 0.09 Zr 0.04 ) Σ12.00 O 19 and the hexagonal P 6 3 / mmc magnetoplumbite-type structure with the cell parameters: a = 5.61(1) Å, c = 22.29(1) Å, V = 608(2) Å 3 , Z = 2. Yeite (TiSi; IMA 2022-079) occurs as irregular-subhedral crystals, 1.2-3.5 μm in size, along with wenjiite (Ti 5 Si 3 ) and zhiqinite (TiSi 2 ) in Ti-Si alloy inclusions in corundum Grain 198c. Yeite has an empirical formula (Ti 0.995 Mn 0.003 V 0.001 Cr 0.001 )(Si 0.996 P 0.004 ) and the orthorhombic Pnma FeB-type structure with the cell parameters: a = 6.55(1) Å, b = 3.64(1) Å, c = 4.99(1) Å, V = 119.0(4) Å 3 , Z = 4. The five minerals are high-temperature oxide or alloy phases, formed in melt pockets in corundum xenocrysts derived from the upper mantle beneath Mt. Carmel.