Dritsite, ideally Li2Al4(OH)12Cl2·3H2O, is a new hydrotalcite supergroup mineral formed as a result of diagenesis in the halite−carnallite rock of the Verkhnekamskoe salt deposit, Perm Krai, Russia. Dritsite forms single lamellar or tabular hexagonal crystals up to 0.25 mm across. The mineral is transparent and colourless, with perfect cleavage on {001}. The chemical composition of dritsite (wt. %; by combination of electron microprobe and ICP−MS; H2O calculated by structure refinement) is: Li2O 6.6, Al2O3 45.42, SiO2 0.11, Cl 14.33, SO3 0.21, H2Ocalc. 34.86, O = Cl − 3.24, total 98.29. The empirical formula based on Li + Al + Si = 6 apfu (atom per formula unit) is Li1.99Al4.00Si0.01[(OH)12.19Cl1.82(SO4)0.01]Σ14.02·2.60(H2O). The Raman spectroscopic data indicate the presence of O–H bonding in the mineral, whereas CO32– groups are absent. The crystal structure has been refined in the space group P63/mcm, a = 5.0960(3), c = 15.3578(13) Å, and V = 345.4(5) Å3, to R1 = 0.088 using single-crystal data. The strongest lines of the powder X-ray diffraction pattern (d, Å (I, %) (hkl)) are: 7.68 (100) (002), 4.422 (61) (010), 3.832 (99) (004, 012), 2.561 (30) (006), 2.283 (25) (113), and 1.445 (26) (032). Dritsite was found as 2H polytype, which is isotypic with synthetic material and shows strong similarity to chlormagalumite-2H. The mineral is named in honour of the Russian crystallographer and mineralogist Prof. Victor Anatol`evich Drits.

A new mineral, krasnoshteinite (Al 8 [B 2 O 4 (OH) 2 ](OH) 16 Cl 4 ·7H 2 O), was found in the Verkhnekamskoe potassium salt deposit, Perm Krai, Western Urals, Russia. It occurs as transparent colourless tabular to lamellar crystals embedded up to 0.06 × 0.25 × 0.3 mm in halite-carnallite rock and is associated with dritsite, dolomite, magnesite, quartz, baryte, kaolinite, potassic feldspar, congolite, members of the goyazite-woodhouseite series, fluorite, hematite, and anatase. D meas = 2.11 (1) and D calc = 2.115 g/cm 3 . Krasnoshteinite is optically biaxial (+), α = 1.563 (2), β = 1.565 (2), γ = 1.574 (2), and 2V meas = 50 (10) • . The chemical composition (wt.%; by combination of electron microprobe and ICP-MS; H 2 O calculated from structure data) is: B 2 O 3 8.15, Al 2 O 3 46.27, SiO 2 0.06, Cl 15.48, H 2 O calc. 33.74, -O=Cl -3.50, totalling 100.20. The empirical formula calculated based on O + Cl = 33 apfu is (Al 7.87 Si 0.01 ) Σ7.88 [B 2.03 O 4 (OH) 2 ][(OH) 15.74 (H 2 O) 0.26 ] Σ16 [(Cl 3.79 (OH) 0.21 ] Σ4 ·7H 2 O. The mineral is monoclinic, P2 1 , a = 8.73980 (19), b = 14.4129 (3), c = 11.3060 (3) Å, β = 106.665 (2) • , V = 1364.35 (5) Å 3 , and Z = 2. The crystal structure of krasnoshteinite (solved using single-crystal data, R 1 = 0.0557) is unique. It is based upon corrugated layers of Al-centered octahedra connected via common vertices. BO 3 triangles and BO 2 (OH) 2 tetrahedra share a common vertex, forming insular [B 2 O 4 (OH) 2 ] 4− groups (this is a novel borate polyanion) which are connected with Al-centered octahedra via common vertices to form the aluminoborate pseudo-framework. The structure is microporous, zeolite-like, with a three-dimensional system of wide channels containing Clanions and weakly bonded H 2 O molecules. The mineral is named in honour of the Russian mining engineer and scientist Arkadiy Evgenievich Krasnoshtein (1937Krasnoshtein ( -2009). The differences in crystal chemistry and properties between high-temperature and low-temperature natural Al borates are discussed.

Newly formed titanium oxides and zircons have been identified in the salt and suprasalt of the Verkhnekamskoye Salt Deposit. These features have been associated with the hydrolysis of clay material and the release of colloidal titanium and zirconium hydroxide during diagenesis, catagenesis, and hypergenesis. This is made possible by sulfate reduction and the acidic environment, which are caused by the radiation–oxidation of Fe2+ from sylvite and carnallite. Anatase is formed both in the suprasalt and salt measures and, only in the lower part of the salt measures, in the rutile. Such a distribution can be associated both with an increase in the degree of catagenetic transformation of salt rocks with depth and with the composition of coexisting sulfate or chloride brines. A typical form of anatase crystals is pinacoid, but this is replaced by a dipyramidal structure in the carnallite zone, which is the location of the most acidic brine. Three types of twins were recorded for rutile, the formation of which is attributable to the growth of a dehydrated colloid of titanium hydroxide on a finely dispersed aggregate. The impurities V, Cr, and Zr (Al, Si, and Fe) established in the titanium oxides reflect the geochemical specialization of the aluminosilicate terrigenous material sources.

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