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Zeolites were synthesized from paper-sludge ash in different alkali solutions. The ash used in this study has a high-Ca content and a low abundance of Si, in part due to the presence of calcite that is used as a paper filler. The major minerals present in the ash are gehlenite ([Ca.sub.2][Al.sub.2]Si[O.sub.7]) and anorthite (Ca[Al.sub.2][Si.sub.2][O.sub.8]). Three kinds of alkali solutions (NaOH, KOH, and LiOH) at four different concentrations (1, 2, 3, and 4 M) were reacted with paper-sludge ash at 90[degrees]C for 24 h. Powder X-ray diffraction showed that hydroxysodalite ([Na.sub.6][Al.sub.6][Si.sub.6][O.sub.24] x [8H.sub.2]O and zeolite Linde F (KAlSi[O.sub.4] x [1.5H.sub.2]O) had formed in NaOH and KOH solutions, respectively, and that anorthite had dissolved in these alkaline solutions, whereas gehlenite had remained unaffected. In the LiOH solution, both anorthite and gehlenite dissolved, and various minerals, including Li-ABW zeolite ([Li.sub.4][Al.sub.6][Si.sub.6][O.sub.16] x [4H.sub.2]O), hydrocalumite [[Ca.sub.2]Al[(OH).sub.6](Cl, OH) x [3H.sub.2]O], tobermorite [Ca.sub.5][Si.sub.6][O.sub.16][(OH).sub.2] x [4H.sub.2]O], katoite [[Ca.sub.3][Al.sub.2](Si[O.sub.4])[(OH).sub.8]], and portlandite [Ca[(OH).sub.2]] formed. The products of mineral synthesis from paper-sludge ash by reaction in alkaline solutions strongly depend on the specific alkali present. Keywords: Paper-sludge ash, hydroxysodalite, zeolite Linde F, Li-ABW, hydrocalumite, tubermorite, katoite, portlandite

To ensure the presence of coesite and its transformed polymorph, quartz, in ultrahigh-pressure (UHP) rocks and to examine the relic of the phase transformation, crystal structures were analyzed by single-crystal X-ray diffraction (XRD) directly using the rock thin section mounted on a slide glass. The rock sample used is a coesite-bearing eclogite from the Sulu UHP terrain, eastern China. The crystal structures were determined successfully by this new method and the presence of coesite and quartz in UHP rocks was identified for the first time by XRD. The R-factor [R(F)] converged to 0.046 for coesite and 0.087 for quartz. The displacement ellipsoids for coesite and quartz are larger than those previously reported for these two phases, which is consistent with expected effects of trapped strain due to the phase transformation from coesite to quartz during exhumation from the Earth's mantle. This paper is the first report of single-crystal XRD of a rock thin section on a glass slide and establishes the technique, and provides proof-of-concept of the method. Although the mineral species included in a thin section can often be identified by other methods, such as Raman spectroscopy, an advantage of the reported method is that it can be applied to any mineral in a thin section, and not just to the UHP minerals. Moreover, it is applicable to an unknown or new mineral in a thin section, discarding the spots of known minerals and constructing a lattice from the residual spots to find the structure of the unknown phase. Keywords: Crystal structure, coesite, quartz, UHP rock, thin section, XRD, displacement ellipsoid

The new minerals carlsonite (IMA2014-067), (NH4)5Fe33+O(SO4)6⋅7H2O, and huizingite-(Al) (IMA2015-014), (NH4)9Al3(SO4)8(OH)2⋅4H2O, formed from a natural fire in an oil-bearing shale near Milan, Ohio. Carlsonite crystals are yellow to orange-brown thick tablets, flattened on {001}, or stout prisms, elongated on [110], up to about 0.5 mm in size. The mineral has a tan streak, vitreous luster, Mohs hardness of 2, brittle tenacity, irregular fracture, perfect {001} cleavage, calculated density of 2.167 g/cm³, and is easily soluble in H2O. Carlsonite is optically biaxial (-), α = 1.576(1), β = 1.585(1), and γ = 1.591(1) (white light). Huizingite-(Al) crystals, typically intergrown in light greenish yellow drusy aggregates, are tabular to bladed, flattened on {100}, up to about 0.25 mm in maximum dimension. The mineral has a white streak, vitreous luster, Mohs hardness of 2%, brittle tenacity, irregular fracture, no cleavage, calculated density of 2.026 g/cm³, and is easily soluble in H2O. Huizingite-(Al) is optically biaxial (+) with α = 1.543(1), β = 1.545(1), and γ = 1.563(1) (589.6 nm light). Raman and infrared spectroscopy was conducted on both minerals. Electron microprobe analyses provided the empirical formulas [(NH4)4.64Na0.24K0.12]Σ5.00Fe3.053+O(SO4)6⋅6.93H2O and [NH4)8.76Na0.22K0.02]Σ9.00(Al1.65Fe1.343+) Σ2.99 (OH)1.98(H2O)4.02(SO4)8.00 for carlsonite and huizingite-(Al), respectively. Huizingite compositions with Fe > Al were noted. Carlsonite is triclinic, P1, a = 9.5927(2), b = 9.7679(3), c = 18.3995(13) Å, α = 93.250(7)°, β = 95.258(7)°, g = 117.993(8)°, V = 1506.15(16) ų, and Z = 2. Huizingite-(Al) is triclinic, PT, a = 9.7093(3), b = 10.4341(3), c = 10.7027(8) Å, α = 77.231(5)°, β = 74.860(5)°, γ = 66.104(5)°, V= 948.73(9) ų, and Z = 1. The five strongest lines in the X-ray powder diffraction pattern of carlsonite are [dobs in Å(I) (hkl)]: 9.23(100)(002); 8.26(40)(100,011); 7.57(43)(111,111,011); 4.93(23)(1 11,120); and 3.144(41)(multiple). Those for huizingite-(Al) are: 8.82(60)(100); 5.04(69)(121); 3.427(100)(2 21); 3.204(68)(211); and 3.043(94)(212,312). The crystal structures of carlsonite (R1 = 0.030) and huizingite (R1 = 0.040) are bipartite, each consisting of a structural unit and an interstitial unit. For carlsonite, the structural unit is a [Fe33+O(H2O)3(SO4)6]5- cluster and the interstitial complex is [(NH4)5(H2O)4]5+. For huizingite-(Al), the structural unit is a [(Al,Fe3+)3(OH)2(H2O)4(SO4)6]5- cluster and the interstitial complex is [(NH4)9(SO4)2]5+. In the carlsonite cluster, three FeO6 octahedra share a common vertex, while in the huizingite-(Al) cluster, three (Al,Fe)O6 octahedra form an abbreviated corner-linked chain. The cluster in carlsonite is the same as that in metavoltine, while the huizingite-(Al) cluster is unique. The range ofLewis basicity of the structural unit in carlsonite is 0.23-0.11 valence units (v.u.) and in huizingite-(Al) it is 0.20-0.12 v.u.; the corresponding Lewis acidities of the interstitial complexes in these structures are 0.13 and 0.14 v.u., respectively. A characteristic Lewis acid strength of 0.13 v.u. is suggested for NH4 when it is in its most typical coordinations of 7 to 8. The close structural relationship between carlsonite and metavoltine and the similarity of their powder diffraction patterns suggests that carlsonite may have misidentified as metavoltine in some NH4-rich mineral assemblages. The new heteropolyhedral cluster in the structure of huizingite-(Al) is of interest because its existence may provide insights into the structural and paragenetic relations among hydrated ferric sulfate minerals. In particular, it may exist as a complex in aqueous solutions or in solid-state transformations involving the formation and/or breakdown of sideronatrite-style [Fe3+(SO4)3]3- chains. We surmise that it may be a more commonly formed mineral than its abundance would indicate and that its rarity may reflect a narrow stability range, and so a transitory existence. [ABSTRACT FROM AUTHOR]