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 (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 P1¯ 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.

as in ophiolites linked to deep subduction along continental plate margins [1][2][3].The origins of these assemblages have sparked debate, with some attributing them to human activities [4].However, the extensively documented xenoliths and xenocrysts discovered in small Cretaceous volcanoes and Plio-Pleistocene gem placer deposits at Mt. Carmel, Israel, play a crucial role in this discussion.The geological context, along with thorough geochemical analysis and precise geochronological data, effectively refute any plausible notion of human interference [3,5,6].Many super-reduced minerals are identified as inclusions within xenoliths composed of corundum aggregates.The relationships between these different phases within melt inclusions have been crucial in interpreting the genesis of super-reduced magma-fluid systems.
Magnéliite (IMA 2021-111), Ti 3+ 2 Ti 4+ 2 O 7 (simply Ti 4 O 7 ), is a new Ti-oxide mineral that corresponds to the first member of the homologous series of Ti-oxides (with Ti n O 2n−1 ), known also as Magnéli phases [15].The name is in honor of Arne Magnéli (1914Magnéli ( -1996)), for his pioneering work on the structural chemistry of transition-metal oxides.
Sassite (IMA 2022-014), Ti 3+ 2 Ti 4+ O 5 (simply Ti 3 O 5 ), is another new Ti-oxide mineral with the Cmcm pseudobrookite-type structure.The name is in honor of Eytan Sass (b. 1932), a geologist at the Freddy and Nadine Herrmann Institute of Earth Sciences, Hebrew University of Jerusalem.He performed the excellent mapping work on Mt.Carmel that identified the various volcanic centers.
Mizraite-(Ce) (IMA 2022-027), Ce(Al 11 Mg)O 19 , is a new Ce-rich oxide mineral belonging to the magnetoplumbite-group [16], with the P6 3 /mmc magnetoplumbite-type structure.The name is after the Mizra river in the Mt.Carmel region, where some corundum xenocrysts investigated in this study (including Grain 198-8) come from alluvial deposits.The tributary Mizra river flows into the Kishon River.
Yeite (IMA 2022-079) is a new alloy mineral, TiSi, with the Pnma FeB-type structure.The name is in honor of Danian Ye (b.1939), a mineralogist at the Institute of Geology and Geophysics, Chinese Academy of Sciences, for his many contributions to mineralogy and crystal chemistry.

Materials and Methods
The corundum xenoliths hosting the new minerals as inclusions occur in the pyroclastic ejecta from small Cretaceous basaltic volcanoes on Mt.Carmel and from placer gemstone deposits found in the terraces of the Paleocene to Pleistocene proto-Kishon river; the modern Kishon River drains Mt.Carmel and the tributary Mizra river and enters the sea near Haifa in northern Israel [2].Much of the xenolith material in the paleoterrace deposits probably also is derived from Miocene and Pliocene basalt outcroppings in the drainage area of the Kishon River.The xenoliths occur as aggregates of skeletal corundum crystals that enclose melt pockets containing reduced mineral assemblages [1,2,17,18].
All the type materials are deposited in the mineralogy collection of the Università degli Studi di Milano, Via Mangiagalli, 34-20133 Milano, Italy.
In order to characterize the composition and structure of the new minerals and associated phases, we used an electron probe microanalyzer (EPMA) and a high-resolution scanning electron microscope (SEM) with an X-ray energy dispersive spectrometer (EDS) and electron backscatter diffraction (EBSD).A ZEISS 1550VP Field-Emission SEM (ZEISS Group, Oberkochen, Germany) with an Oxford X-Max EDS was used for backscatter electron (BSE) imaging and fast elemental analysis.Quantitative WDS elemental microanalyses of the new minerals were carried out using a JEOL 8200 EPMA (JEOL Ltd., Tokyo, Japan) (15 kV and 10 nA, focused beam) and processed with the CITZAF correction procedure [19].The focused electron beam is ~150 nm in diameter.
EBSD analyses at a submicrometer scale were performed using methods described by [20,21] for studies of micron-sized new minerals.An HKL EBSD system on the ZEISS 1550VP Field-Emission SEM was operated at 20 kV and 6 nA in focused beam mode with a 70 • tilted stage and in a variable pressure mode (25 Pa).The EBSD system was calibrated using a single-crystal silicon standard.Experimental EBSD patterns allowed the collection of structural information and cell constants that were derived by matching with those of the structures of synthetic phases from the ICSD (Inorganic Crystal Structure Database).
Due to the small size of the samples, most of the physical properties (optical, hardness, fracture, cleavage, habit, density, etc.) were impossible to obtain.
The chemical composition of magnéliite using EPMA (Table 1) shows an empirical formula (based on 7 O pfu) of (Ti 3+   The EBSD patterns can be indexed only by the P -1 Ti4O7-type structure and match the synthetic Ti4O7 cell from [23] (Figure 2), with a mean angular deviation of 0.32°-0.35°,revealing the following cell parameters: a = 5.60  Magnéliite (Ti 3+ 2 Ti 4+ 2 O 7 ) is a new Ti-oxide mineral.It belongs to the so-called Magnéli phases, i.e., a series of Ti-oxides homologous with Ti n O 2n−1 (with n = from 4 to 10).The first member of the series, synthetic Ti 4 O 7 , is well known (e.g., [23][24][25]).The crystal structure of magnéliite can be considered to be derived from the structure of rutile TiO 2 by crystallographic shear of the (121) rutile plane with a 1/2[0-11] rutile vector every four octahedra of rutile [26].The resulting structure has chains of edge-sharing TiO 6 octahedra truncated every four octahedra by the crystallographic shear planes (Figure 3).At room-T, Ti 3+ and Ti 4+ are disordered among the eight symmetrically independent positions, while at T < 120 K, Ti 3+ and Ti 4+ are arranged in an ordered fashion to form a Ti 3+ -Ti 4+ pair (bipolarons) and the material becomes a nonmagnetic insulator.Recent data by [26] show that even at room-T some local ordering of Ti 3+ -Ti 3+ and Ti 4+ -Ti 4+ pairs exists.Magnéliite (Ti 3+ 2Ti 4+ 2O7) is a new Ti-oxide mineral.It belongs to the so-called Magnéli phases, i.e., a series of Ti-oxides homologous with TinO2n-1 (with n = from 4 to 10).The first member of the series, synthetic Ti4O7, is well known (e.g., [23][24][25]).The crystal structure of magnéliite can be considered to be derived from the structure of rutile TiO2 by crystallographic shear of the (121)rutile plane with a 1/2[0-11]rutile vector every four octahedra of rutile [26].The resulting structure has chains of edge-sharing TiO6 octahedra truncated every four octahedra by the crystallographic shear planes (Figure 3).At room-T, Ti 3+ and Ti 4+ are disordered among the eight symmetrically independent positions, while at T < 120 K, Ti 3+ and Ti 4+ are arranged in an ordered fashion to form a Ti 3+ -Ti 4+ pair (bipolarons) and the material becomes a nonmagnetic insulator.Recent data by [26] show that even at room-T some local ordering of Ti 3+ -Ti 3+ and Ti 4+ -Ti 4+ pairs exists.

Mizraite-(Ce)
Mizraite-(Ce) occurs with Ce-silicate and Ti-sulfide in melt pockets between dum and spinel within Grain 198-8 (Figure 10).Other inclusions in this corundum contain Ti,Al,Zr-oxide, ziroite, baddeleyite, thorianite, osbornite, zangboite (T wenjiite (Ti5Si3), and a [(Mn,Fe,Ti,V,Cr)4Ti2]Si5 alloy.The mineral occurs as euhedra tals < 1-14 µm in size.It is transparent with a light bluish-green color.The Glad Dale relationship gives n = 1.828.Mizraite-(Ce) (Table 4) exhibits an empirical formula (based on 19 O pfu) of (Ce0.76Ca0.10La0.07Nd0.01)Σ0.94(Al10.43Mg0.84Ti3+ 0.60Si0.09Zr0.04)Σ12.00O19.The simplified formula is The EBSD pa erns can be indexed only by the hexagonal P63/mmc magnetoplumbite structure and match the Ce-bearing hibonite cell of [40] (Figure 11), with a mean angular deviation of 0.32°-0.37°,revealing the following cell parameters: a = 5.61(1) Å, c = 22.29(1) Å, V = 608(2) Å 3 , and Z = 2.The calculated density is 4.16 g•cm −3 using the empirical formula and the unit-cell volume estimated from the EBSD data.Mizraite-(Ce) is the Ce-analog of hibonite, and is a new member of the magnetoplumbite group (A[B12]O19; [16]); it is the first member presenting the heterovalent substitution A 2+ + B 3+ → A 3+ + B 2+ (Ca 2+ + Al 3+ → REE 3+ + Mg 2+ ) as the dominant species-defining exchange.Whenever another magnetoplumbite REE-dominant mineral is described, it  [40,44].Reported here is the first natural occurrence of Ce(Al 11 Mg)O 19 , although zoned "hibonite" grains with REE-rich cores (ΣREE > 0.6 atoms per formula unit) have been described by [45] where kalsilite, leucite, and hibonite occur together with spinel, corundum, sphene, perovskite, Ti-phlogopite, and K-feldspar in a granulite-facies gneiss in the Punalur district in Kerala, southern India.The structure of mizraite-(Ce) has the topology of the magnetoplumbite group minerals with Ln 3+ (Al 11 M 2+ )O 19 stoichiometry and is made of two structural layers: the hexagonal close-packed R-block, containing the Ln 3+ site, the trigonal bipyramidal M2 site, and the octahedral face-sharing M4 site; and the cubic close-packed S-block, containing layers of M5 octahedra interspaced by the M3 tetrahedra and the M1 octahedra (Figure 12).The spinel blocks contain most of the Al 3+ in the M1 and M5 sites, and M 2+ cations are distributed among the octahedral and tetrahedral sites.The Ln 3+ and remaining Al 3+ cations are localized in mirror planes, whereas M4 octahedra containing high-charge small cations lie on both sides of the mirror plane (Figure 12).The separation between the two Ln 3+ sites of the same mirror plane is equal to the a unit cell parameter (ca.5.6 Å), whereas between two different mirror planes it is approximately 11 Å. localized in mirror planes, whereas M4 octahedra containing high-charge small cations lie on both sides of the mirror plane (Figure 12).The separation between the two Ln 3+ sites of the same mirror plane is equal to the a unit cell parameter (ca.5.6 Å), whereas between two different mirror planes it is approximately 11 Å.

Discussion
The oxide minerals described here are high-temperature phases.They crystallized from melts that were trapped in intracrystalline and interstitial voids in aggregates of corundum crystals [2].The whole suite of corundum xenoliths is characterized by oxygen fugacity (fO2) below the levels normally encountered in Earth s upper mantle or crust (IW to IW-9; [50]).We recognize three broad paragenetic types.
Crn-A: these are hopper to skeletal crystals showing strong zoning in Ti due to the uptake of Ti 3+ during rapid crystal growth [51].The composition of the trapped melts is Ca-Mg-Al silicates showing high contents of S as well as incompatible elements.Phase The structure of yeite (using the atom coordinates published by [46]).SiTi 7 capped triangular prims in blue.The polyhedra share edges.Figure obtained using Vesta 3.0 [27].

Discussion
The oxide minerals described here are high-temperature phases.They crystallized from melts that were trapped in intracrystalline and interstitial voids in aggregates of corundum crystals [2].The whole suite of corundum xenoliths is characterized by oxygen fugacity (f O 2 ) below the levels normally encountered in Earth's upper mantle or crust (IW to IW-9; [50]).We recognize three broad paragenetic types.
Crn-A: these are hopper to skeletal crystals showing strong zoning in Ti due to the uptake of Ti 3+ during rapid crystal growth [51].The composition of the trapped melts is Ca-Mg-Al silicates showing high contents of S as well as incompatible elements.Phase assemblages reflect low f O 2 , with all Ti as Ti 3+ (e.g., tistarite).
Crn-B: these are large homogeneous (unzoned) corundum crystals, which typically show Ti contents > 1 wt%.In these crystals, interstitial pockets contain small amounts of glass, which are typically high in REE, Zr, and other incompatible elements.In phenocrysts, Ti is present as both Ti 3+ and Ti 4+ .
Crn-C: these are texturally similar to Crn-B; however, the Ti contents in corundum are typically low (<0.5 wt% Ti).Rare glasses are rich in LREE and Ba.The presence of more Ti 4+ phases (rutile, griffinite) suggests higher mean f O 2 than in Crn-A and Crn-B.Hibonite occurs in all three parageneses; in Crn-A and Crn-B, it contains high levels of Ti 3+ , whereas in Crn-C, the Ti 3+ contents are very low.
Magnéliite, sassite, and ziroite are members of a large population of Ti-Al-Zr phases, which include carmeltazite, griffinite, tistarite, rutile, "Allende-like" Ti-Zr-Al oxide [35], kaitianite [52], and many as yet undescribed minerals (Figure 16).Part of this variety is due to the presence of Ti as both Ti 3+ and Ti 4+ , reflecting the differences in f O 2 among the three parageneses.Individual phases may show large ranges in solid solution, reflecting substitutions of trivalent (Ti 3+ , Al) and quadrivalent (Ti 4+ , Zr) ions.Magnéliite shows some solid solution of both ZrO2 and Al2O3 (Table 1); it has crystallized from a glass, residual after the crystallization of large hibonite crystals.The type magnéliite is associated with alabandite, which suggests that both crystallized during the ascent of the xenoliths as decreasing pressure led to lower solubility of sulfur in the melt.This assemblage and the low Ti in corundum (0.4 wt% Ti) are characteristic of paragenesis Crn-C.
Sassite is clearly a liquidus phase (Figure 4) together with a Ti-Al-Zr oxide and corundum; the reconstructed melt in these interstitial pockets is low in Si and Ca and very high in Ti, while the residual melt is Al, Si-rich.Sassite shows a very wide range of solid solution toward griffinite (Al2TiO5 [14]; Figure 16).The presence of alabandite and baddeleyite suggests quench crystallization during ascent of the xenolith, which is consistent with the quench crystallization of mullite at low P.This is a typical Crn-B paragenesis.Magnéliite shows some solid solution of both ZrO 2 and Al 2 O 3 (Table 1); it has crystallized from a glass, residual after the crystallization of large hibonite crystals.The type magnéliite is associated with alabandite, which suggests that both crystallized during the ascent of the xenoliths as decreasing pressure led to lower solubility of sulfur in the melt.This assemblage and the low Ti in corundum (0.4 wt% Ti) are characteristic of paragenesis Crn-C.
Sassite is clearly a liquidus phase (Figure 4) together with a Ti-Al-Zr oxide and corundum; the reconstructed melt in these interstitial pockets is low in Si and Ca and very high in Ti, while the residual melt is Al, Si-rich.Sassite shows a very wide range of solid solution toward griffinite (Al 2 TiO 5 [14]; Figure 16).The presence of alabandite and baddeleyite suggests quench crystallization during ascent of the xenolith, which is consistent with the quench crystallization of mullite at low P.This is a typical Crn-B paragenesis.
Ziroite can have a significant solid solution of TiO 2 (Table 3; Figure 16).The ability of ziroite to take up Ti can explain the coexistence of ziroite and baddeleyite (Figure 7), as the latter does not appear to take up much Ti.Like sassite, the type ziroite has crystallized from a Ca-Mg-Al-silicate glass, residual after the crystallization of hibonite and a Ti-Al-Zr oxide, in a typical Crn-B paragenesis.
Mizraite-(Ce) is also clearly a liquidus phase, crystallizing from a residual melt high in LREE and S. Its occurrence as interstitial to large exsolved spinel grains suggests that it belongs to paragenesis Crn-B, although the low Ti content of the adjacent corundum (0.4 wt%) is more characteristic of Crn-C.
The study of mixed-valence phases in paragenesis Crn-B, and possibly in Crn-C, provides new information on the interpretation of the origins of the Mt.Carmel corundumaggregate xenoliths.While the different parageneses share many common features, it has proven difficult to establish common lines of descent between them.
The alloy phases, including yeite as described here, appear as inclusions in aggregates of corundum crystals; they represent trapped melts, melts + crystals, and subsolidus assemblages that formed from the melts on cooling, both prior to eruption and during quenching upon eruption of the host basalts [6].The immiscible separation of these melts from the coexisting silicate melt under highly reducing conditions allowed the crystallization of Fe-free phases from the silicate melt(s).The chemistry and evolution of these melts through multiple stages of immiscibility have been described in [6]; yeite adds more detail to this picture.
Yeite occurs in spheroidal balls (Figure 13) interpreted as immiscible melts coexisting with the silicate melt from which the enclosing corundum was crystallizing.The smooth, straight, or irregular boundaries between yeite, wenjiite, and zhiqinite suggest that the original melt may have decomposed into mutually immiscible melts or crystallized into the three coexisting phases.However, examination of the phase diagram for the Ti-Si Si binary [53] suggests that the situation was more complex (Figure 17).This binary is separated into two subsystems by a thermal divide at Ti 3 Si 2 ; the assemblage TiSi+TiSi 2 appears (crystallizes) at a eutectic point (1743 K) on the Si side of the divide, while wenjiite crystallizes from melts on the Ti side of the divide from 2400 K to a eutectic (L → Ti + Ti 5 Si 3 ) at 1613 K.There is no point at which TiSi coexists with Ti 5 Si 3 .However, the average reconstructed composition of the melts in Figure 13 lies near several cotectics (1773-1673 K) in the Fe-Ti-Si ternary system (Figure 18) [54], making it probable that three phases may have crystallized from the melt over a very short T range in the high-temperature part of this ternary system.As noted by [6], the temperatures in the natural system beneath Mt.Carmel probably were lower than those in the synthetic systems due to the coexistence of a fluid phase rich in H 2 , which can lower temperatures in metallic systems by up to several hundred degrees [55].
These alloy minerals thus illustrate the wide range of immiscible-melt compositions and crystallization conditions captured in the xenoliths from Mt. Carmel and give some new insights into processes in this highly reduced magmatic system.This highly reduced corundum-related assemblage is not simply a one-locality oddity; very similar associations have been reported from the Luobusa ophiolite in SE Tibet [48,49] and from many other localities in intraplate and subduction-zone tectonic settings [2,6].These occurrences imply a significant role for mantle-derived CH 4 +H 2 fluids in magmatic processes.
straight, or irregular boundaries between yeite, wenjiite, and zhiqinite suggest that the original melt may have decomposed into mutually immiscible melts or crystallized into the three coexisting phases.However, examination of the phase diagram for the Ti-Si Si binary [53] suggests that the situation was more complex (Figure 17).This binary is separated into two subsystems by a thermal divide at Ti3Si2; the assemblage TiSi+TiSi2 appears (crystallizes) at a eutectic point (1743 K) on the Si side of the divide, while wenjiite crystallizes from melts on the Ti side of the divide from 2400K to a eutectic (L → Ti + Ti5Si3) at 1613 K.There is no point at which TiSi coexists with Ti5Si3.However, the average reconstructed composition of the melts in Figure 13 lies near several cotectics (1773-1673 K) in the Fe-Ti-Si ternary system (Figure 18) [54], making it probable that three phases may have crystallized from the melt over a very short T range in the high-temperature part of this ternary system.As noted by [6], the temperatures in the natural system beneath Mt.Carmel probably were lower than those in the synthetic systems due to the coexistence of a fluid phase rich in H2, which can lower temperatures in metallic systems by up to several hundred degrees [55].These alloy minerals thus illustrate the wide range of immiscible-melt compositions and crystallization conditions captured in the xenoliths from Mt. Carmel and give some new insights into processes in this highly reduced magmatic system.This highly reduced corundum-related assemblage is not simply a one-locality oddity; very similar associations have been reported from the Luobusa ophiolite in SE Tibet [48,49] and from many other localities in intraplate and subduction-zone tectonic settings [2,6].These occurrences imply a significant role for mantle-derived CH4+H2 fluids in magmatic processes.

Conclusions
Reported here is the discovery of five new minerals, magnéliite (Ti

Materials 2023 , 22 Figure 2 .
Figure 2. (left) EBSD pa erns of the magnéliite crystal in Figure 1 at different orientations, and (right) the pa erns indexed with the P -1 Ti4O7-type structure.Blue cross marks the pa ern center.

Figure 2 . 22 Figure 3 .
Figure 2. (left) EBSD patterns of the magnéliite crystal in Figure 1 at different orientations, and (right) the patterns indexed with the P1 Ti 4 O 7 -type structure.Blue cross marks the pattern center.

Figure 3 .
Figure 3. Detail of the structure of magnéliite (using the atom coordinates form Marezio and Dernier, 1971) projected onto (−556), showing the chains of four-member units of edge-sharing Ti-centered octahedra.Figure obtained using Vesta 3.0 [27].

Figure 3 .
Figure 3. Detail of the structure of magnéliite (using the atom coordinates form Marezio and Dernier, 1971) projected onto (−556), showing the chains of four-member units of edge-sharing Ti-centered octahedra.Figure obtained using Vesta 3.0 [27].

Materials 2023 , 22 Figure 5 .
Figure 5. (left) EBSD patterns of the ziroite crystals in Figure 3, and (right) the patterns indexed with the P42/nmc zirconia(HT)-type.Blue cross marks the pattern center.

Figure 5 .
Figure 5. (left) EBSD patterns of the ziroite crystals in Figure 4, and (right) the patterns indexed with the P4 2 /nmc zirconia(HT)-type.Blue cross marks the pattern center.

Figure 8 .
Figure 8. (left) EBSD patterns of two sassite crystals in Figure 5, and (right) the patterns indexed with the Cmcm pseudobrookite-type Ti3O5 structure.Blue cross marks the pattern center.

Figure 8 .
Figure 8. (left) EBSD patterns of two sassite crystals in Figure 7, and (right) the patterns indexed with the Cmcm pseudobrookite-type Ti 3 O 5 structure.Blue cross marks the pattern center.

Figure 11 .
Figure 11.(left) EBSD pa erns of two mizraite-(Ce) crystals in Figure 7, and (right) the pa erns indexed with the P63/mmc hibonite structure.Blue cross marks the pa ern center.

Figure 11 .
Figure 11.(left) EBSD patterns of two mizraite-(Ce) crystals in Figure 10, and (right) the patterns indexed with the P6 3 /mmc hibonite structure.Blue cross marks the pattern center.Mizraite-(Ce) is the Ce-analog of hibonite, and is a new member of the magnetoplumbite group (A[B 12 ]O 19 ; [16]); it is the first member presenting the heterovalent substitution A 2+ + B 3+ → A 3+ + B 2+ (Ca 2+ + Al 3+ → REE 3+ + Mg 2+ ) as the dominant species- defining exchange.Whenever another magnetoplumbite REE-dominant mineral is described, it would represent a new subgroup along with the magnetoplumbite (A = Pb), hawthorneite (A = Ba), and hibonite (A = Ca) subgroups.Hibonite has a general formula of (Ca,Ce)(Al,Ti,Mg) 12 O 19 and an ideal formula of CaAl 12 O 19 .Synthetic Ce(Al 11 Mg)O 19 is not reported, whereas La(Al 11 Mg)O 19 , La(Al 11 Mn)O 19 , and La(Al 11 Ni)O 19 with the hibonite structure have been synthesized [41-43].Terrestrial hibonite often contains minor Ce and other REEs and has a general formula of (Ca,Ce)(Al,Ti,Mg) 12 O 19[40,44].Reported here is the first natural occurrence of Ce(Al 11 Mg)O 19 , although zoned "hibonite" grains with REE-rich cores (ΣREE > 0.6 atoms per formula unit) have been described by[45] where kalsilite, leucite, and hibonite occur together with spinel, corundum, sphene, perovskite, Ti-phlogopite, and K-feldspar in a granulite-facies gneiss in the Punalur district in Kerala, southern India.The structure of mizraite-(Ce) has the topology of the magnetoplumbite group minerals with Ln 3+ (Al 11 M 2+ )O 19 stoichiometry and is made of two structural layers: the hexagonal close-packed R-block, containing the Ln 3+ site, the trigonal bipyramidal M2 site, and the octahedral face-sharing M4 site; and the cubic close-packed S-block, containing layers of M5 octahedra interspaced by the M3 tetrahedra and the M1 octahedra (Figure12).The spinel blocks contain most of the Al 3+ in the M1 and M5 sites, and M 2+ cations are distributed among the octahedral and tetrahedral sites.The Ln 3+ and remaining Al 3+ cations are localized in mirror planes, whereas M4 octahedra containing high-charge small cations lie on both sides of the mirror plane (Figure12).The separation between the two Ln 3+ sites of the same mirror plane is equal to the a unit cell parameter (ca.5.6 Å), whereas between two different mirror planes it is approximately 11 Å.

Figure 12 .
Figure 12.Detail of magnetoplumbite-type structure of mizraite-(Ce), showing the interlayering of S-and R-blocks.Ln 3+ cations are located in the R-blocks along with the M2 and M4 sites.Figure obtained using Vesta 3.0 [27].

Figure 12 .
Figure 12.Detail of magnetoplumbite-type structure of mizraite-(Ce), showing the interlayering of Sand R-blocks.Ln 3+ cations are located in the R-blocks along with the M2 and M4 sites.Figure obtained using Vesta 3.0 [27].

Figure 14 .
Figure 14.(left) EBSD patterns of yeite in Figure 3 at different orientations, and (right) the patterns indexed with the Pnma TiSi structure.Blue cross marks the pattern center.

Figure 14 .
Figure 14.(left) EBSD patterns of yeite in Figure 13 at different orientations, and (right) the patterns indexed with the Pnma TiSi structure.Blue cross marks the pattern center.
ziroite (ZrO 2 ), sassite (Ti 3+ 2 Ti 4+ O 5 ), mizraite-(Ce) (Ce(Al 11 Mg)O 19 ), and yeite (TiSi), in melt inclusions in corundum xenocrysts from the Mt.Carmel area, Israel.The description of their chemical composition and the crystal structures of the synthetic analogues that match the EBSD data is provided.Many physical properties cannot be obtained because of the extremely reduced dimensions of the grains (nano scale), but the data are sufficient to support their correct identification.These minerals are high-temperature oxide or alloy
* Total titanium has been partitioned between Ti 3+ and Ti 4+ for charge balance to make ideal stoichiometry.
* Total titanium has been partitioned between Ti 3+ and Ti 4+ for charge balance to achieve ideal stoichiometry.
* Titanium has been assigned to be Ti 3+ for charge balance to achieve best stoichiometry.