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During our nanomineralogical investigation of melt inclusions in corundum xenocrysts from the Mount Carmel area, Israel, seven new oxide and alloy minerals have been discovered since 2021. Herein, we report toledoite (TiFeSi; IMA 2022-036), a new alloy mineral. Toledoite occurs as irregular crystals 2–16 μm in size, with gupeiite (Fe3Si), jingsuiite (TiB2), ziroite (ZrO2), osbornite (TiN), xifengite (Fe5Si3), and naquite (FeSi) in corundum Grain WG1124E-1. Toledoite has an empirical formula (Ti0.83Cr0.07Mn0.06V0.02)(Fe0.96Mn0.04)(Si0.99P0.04) and an orthorhombic Ima2 TiFeSi-type structure with the following cell parameters: a = 7.00(1) Å, b = 10.83(1) Å, c = 6.29(1) Å, V = 477(1) Å3, Z = 12. Toledoite is a high-temperature alloy phase, formed under extremely reduced conditions in melt pockets in corundum xenocrysts derived from the upper mantle beneath Mount Carmel in Israel. The name was given in honor of Vered Toledo, of Shefa Gems Ltd. for her support and for providing corundum xenocrysts from the Mount Carmel region for this investigation of new minerals. [ABSTRACT FROM AUTHOR]

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 (Ti3+2Ti4+2O7; 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 (Ti3+1.66Al0.13Ti4+0.15Mg0.10Ca0.01Sc0.01)Σ2.06 (Ti4+1.93Zr0.08)Σ2.01O7 and the triclinic P 1 ¯ Ti4O7-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) Å3, Z = 4. Ziroite (ZrO2; 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 (Zr0.72Ti4+0.26Mg0.02Al0.02Hf0.01)Σ1.03O2 and the tetragonal P42/nmc zirconia(HT)-type structure with the cell parameters: a = 3.60(1) Å, c = 5.18(1) Å, V = 67.1(3) Å3, Z = 2. Sassite (Ti3+2Ti4+O5; 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 (Ti3+1.35Al0.49Ti4+0.08Mg0.07)Σ1.99(Ti4+0.93Zr0.06Si0.01)Σ1.00O5 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) Å3, Z = 4. Mizraite-(Ce) (Ce(Al11Mg)O19; 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 (Ce0.76Ca0.10La0.07Nd0.01)Σ0.94(Al10.43Mg0.84Ti3+0.60Si0.09Zr0.04)Σ12.00O19 and the hexagonal P63/mmc magnetoplumbite-type structure with the cell parameters: a = 5.61(1) Å, c = 22.29(1) Å, V = 608(2) Å3, Z = 2. Yeite (TiSi; IMA 2022-079) occurs as irregular-subhedral crystals, 1.2–3.5 μm in size, along with wenjiite (Ti5Si3) and zhiqinite (TiSi2) in Ti-Si alloy inclusions in corundum Grain 198c. Yeite has an empirical formula (Ti0.995Mn0.003V0.001Cr0.001)(Si0.996P0.004) 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) Å3, 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. [ABSTRACT FROM AUTHOR]

Griffinite (IMA 2021-110), ideally Al2TiO5, is a new mineral from inclusions in corundum xenocrysts from the Mount Carmel area, Israel. It occurs as subhedral crystals, ~1–4 μm in size, together with Zr-rich rutile within a corundum grain. In this study, a mean of eight electron probe microanalyses gave TiO2 44.41 (24), Al2O3 55.13 (18), FeO 0.47 (5), and MgO 0.37 (2), totaling 100.38 wt%, which corresponded, on the basis of a total of five oxygen atoms, to (Al1.97Mg0.02Fe0.01)Ti1.01O5. Electron back-scatter diffraction studies revealed that griffinite is orthorhombic and in the space group Cmcm, with a = 3.58 (2) Å, b = 9.44 (1) Å, c = 9.65 (1) Å, and V = 326 (2) Å3 with Z = 4. The six strongest calculated powder diffraction lines [d in Å (I/I0) (hkl)] are 3.347 (100) (110); 2.658 (90) (023); 4.720 (77) (020); 1.903 (57) (043); 1.790 (55) (200); and 1.688 (44) (134). In the crystal structure, Al3+ and Ti4+ are disordered into two distinct distorted octahedra, which form edge-sharing double chains. Griffinite is a high-temperature oxide mineral, formed in melt pockets in corundum-aggregate xenoliths derived from the upper mantle beneath Mount Carmel, Israel. The new mineral is named after William L. Griffin, a geologist at Macquarie University, Australia. [ABSTRACT FROM AUTHOR]

Our nanomineralogical investigation of melt inclusions in corundum xenoliths from the Mount Carmel area, Israel, has revealed seven IMA-approved new minerals since 2021. We report here the first terrestrial occurrence of kaitianite (Ti3+2Ti4+O5). Kaitianite occurs as exsolution lamellae in tistarite (Ti2O3), in a melt inclusions together with a Ti,Al,Zr-oxide, a MgTi3+2Al4SiO12 phase, spinel, sapphirine, Ti-sulfide, alabandite, and Si-rich glass in a corundum grain (Grain 1125C2). The chemical composition of kaitianite using electron probe microanalysis is (wt%) Ti2O3 58.04, TiO2 37.82, Al2O3 2.87, MgO 0.85, ZrO2 0.10, CaO 0.02, SiO2 0.02, sum 99.73, yielding an empirical formula of (Ti3+1.78Al0.12Ti4+0.05Mg0.05)(Ti4+1.00)O5, with the Ti3+ and Ti4+ partitioned, assuming a stoichiometry of three cations and five oxygen anions pfu. Electron back-scatter diffraction reveals that kaitianite has the monoclinic C2/c γ-Ti3O5-type structure with cell parameters: a = 10.12 Å, b = 5.07 Å, c = 7.18 Å, β = 112°, V = 342 Å3, and Z = 4. Kaitianite is a high-temperature oxide phase, formed in melt pockets under reduced conditions in corundum-aggregate xenoliths derived from the upper mantle beneath Mount Carmel, Israel. [ABSTRACT FROM AUTHOR]