Israël: une société minière découvre un minéral inconnu
Carmeltazite: A New Unique Gemstone From Israel
▻https://www.forbes.com/sites/davidbressan/2019/01/14/carmeltazite-a-new-unique-gemstone-from-israel
There are currently over 5,500 known minerals on Earth, with around 100 new minerals being added to the list each year. Most are quite unspectacular in appearance, with crystals too small to be used in jewelry or too rare to be of any economic interest.
Last week, the International Mineralogical Association recognized carmeltazite as a new, distinct mineral. The mineral was named after Mount Carmel where it was found and the elements it contains - Titanium, Aluminum and Zirconium.
Minerals | Free Full-Text | Carmeltazite, ZrAl2Ti4O11, a New Mineral Trapped in Corundum from Volcanic Rocks of Mt Carmel, Northern Israel
▻https://www.mdpi.com/2075-163X/8/12/601
The new mineral species carmeltazite, ideally ZrAl2Ti4O11, was discovered in pockets of trapped melt interstitial to, or included in, corundum xenocrysts from the Cretaceous Mt Carmel volcanics of northern Israel, associated with corundum, tistarite, anorthite, osbornite, an unnamed REE (Rare Earth Element) phase, in a Ca-Mg-Al-Si-O glass. In reflected light, carmeltazite is weakly to moderately bireflectant and weakly pleochroic from dark brown to dark green. Internal reflections are absent. Under crossed polars, the mineral is anisotropic, without characteristic rotation tints. Reflectance values for the four COM wavelengths (Rmin, Rmax (%) (λ in nm)) are: 21.8, 22.9 (471.1); 21.0, 21.6 (548.3), 19.9, 20.7 (586.6); and 18.5, 19.8 (652.3). Electron microprobe analysis (average of eight spot analyses) gave, on the basis of 11 oxygen atoms per formula unit and assuming all Ti and Sc as trivalent, the chemical formula (Ti3+3.60Al1.89Zr1.04Mg0.24Si0.13Sc0.06Ca0.05Y0.02Hf0.01)Σ=7.04O11. The simplified formula is ZrAl2Ti4O11, which requires ZrO2 24.03, Al2O3 19.88, and Ti2O3 56.09, totaling 100.00 wt %. The main diffraction lines, corresponding to multiple hkl indices, are (d in Å (relative visual intensity)): 5.04 (65), 4.09 (60), 2.961 (100), 2.885 (40), and 2.047 (60). The crystal structure study revealed carmeltazite to be orthorhombic, space group Pnma, with unit-cell parameters a = 14.0951 (9), b = 5.8123 (4), c = 10.0848 (7) Å, V = 826.2 (1) Å3, and Z = 4. The crystal structure was refined to a final R1 = 0.0216 for 1165 observed reflections with Fo > 4σ(Fo). Carmeltazite exhibits a structural arrangement similar to that observed in a defective spinel structure. The name carmeltazite derives from Mt Carmel (“CARMEL”) and from the dominant metals present in the mineral, i.e., Titanium, Aluminum and Zirconium (“TAZ”). The mineral and its name have been approved by the IMA Commission on New Minerals, Nomenclature and Classification (2018-103)
Shefa Yamim’s Carmel Sapphire™ formed of a new and rare mineral
▻https://www.shefayamim.com/shefa-yamim-s-carmel-sapphire-formed-of-a-new-and-rare-mineral
Shefa Yamim (LSE: SEFA), a precious stone exploration company in Northern Israel, is pleased to announce that carmeltazite, a mineral found in one of its gemstones, the Carmel Sapphire™, has been recognised and approved as a new mineral by the International Mineralogical Association ("IMA") Commission on New Minerals, Nomenclature and Classification.
The new mineral, first discovered by Shefa Yamim, was named carmeltazite due to its location of discovery on Mt Carmel ("CARMEL"), and due to its major chemical components, namely, Titanium, Aluminum and Zirconium ("TAZ"). The mineral is part of the remarkable mineral assemblage found as tiny inclusions inside Shefa Yamim’s unique gemstone, the Carmel Sapphire™.
As stated in a published article entitled Carmeltazite, ZrAl2Ti4O11, a New Mineral Trapped in Corundum from Volcanic Rocks of Mt Carmel, Northern Israel, the mineral and its name have been approved by the IMA under the number 2018-103. The article was written by scientists from Macquarie University, the University of Western Australia, Università degli Studi di Firenze, Università degli Studi di Milano and Shefa Yamim.
