Hazenite, KNaMg2(PO4)2{middle dot}14H2O, a new biologically related phosphate mineral, from Mono Lake, California, U.S.A.

Abstract

A new biologically related, struvite-type phosphate mineral, hazenite, ideally KNaMg 2 (PO 4 ) 2 ⋅14H 2 O, has been found in and/or on completely dried-out or decomposed cyanobacteria on porous calciumcarbonate (mainly calcite and aragonite) substrates in Mono Lake, California. The mineral occurs as radiating clusters of prismatic crystals and is colorless, transparent with white streak and vitreous luster. It is brittle, with the Mohs hardness of 2∼2.5; cleavage is good on {001} and no twinning was observed. The measured and calculated densities are 1.91(3) and 1.88(2) g/cm 3 , respectively. Hazenite is biaxial (+), with n α =1.494(1), n β = 1.498(1), n γ = 1.503(1), 2V meas = 41 (2)°, 2V calc = 42°, X = b, Y = c, Z = a, and does not fluoresce under long-or short-wave ultraviolet rays. The dispersion is strong with r < v. It is soluble in water. The electron microprobe analysis yielded an empirical formula of K 0.97 (Na 0.96 Ca 0.02 )Mg 2.07 [(P 0.98 S 0.02 )O 4 ] 2 ⋅13.90H 2 O. Hazenite is orthorhombic with space group Pmnb and unit-cell parameters a = 6.9349(4) Å, b = 25.174(2) Å, c = 11.2195(8) Å, and V = 1958.7(3) Å 3 .There are many structural similarities between hazenite and struvite, as also revealed by their Raman spectra. The hazenite structure contains six symmetrically independent non-hydrogen cation sites, two for Mg 2+ (Mg1 and Mg2), two for P 5+ (P1 and P2), one for Na + , and one for K + . It can be viewed as three types of layers stacking along the b-axis, in a repeating sequence of ABCBABCB…, where layer A consists of Mg1(H 2 O) 6 octahedra and NaO 6 trigonal prisms, layer B of P1O 4 and P2O 4 tetrahedra, and layer C of Mg2(H 2 O) 6 octahedra and very irregular KO 6 polyhedra. These layers are linked together by hydrogen bonds, plus the K-O bonds between layers B and C (K-O5-P2). Interestingly, the combination of layers B and C in hazenite exhibits a configuration analogous to the struvite-(K) structure. Hazenite is believed to form in high pH environments through the involvement of cyanobacterial activities. To our knowledge, hazenite is the first struvite-type compound that contains two structurally distinct monovalent cations (K and Na), pointing to an exclusive role of biological activity in the mineralization process.

Carbapenem-Resistant Acinetobacter baumannii Recovered from Swine Manure

“…For example, struvite-(K) contains potassium instead of ammonium, while hazenite is the first struvite-type compound that contains two structurally distinct monovalent cations (K and Na). 23 As for the content of the selected macro-and microelements (Table 1), Cu and Zn concentrations were high; 88 and 679 mg/kg, respectively.…”

Flower-like apatite recording microbial processes through deep geological time and its implication to the search for mineral records of life on Mars

“…On the one hand, the phosphorus-containing organic compounds (e.g., phospholipids) in cells could supply phosphorus for phosphate precipitation (Yang and Sun 2004;Yang et al 2011). On the other hand, biomass of algae and animal tissue (e.g., algal cell and acritarch vesicles) could provide abundant nucleation sites for the heterogeneous nucleation of phosphate (Wilby et al 1996;Yang and Sun 2004;Xiao and Schiffbauer 2008;Yang et al 2011). The widely observed organic grains and organic microlayers alternating with fabric phosphatized organisms in Niutitang phosphatic nodules evidenced the biological activities during phosphatization processes.…”

Phosphorus recovery from urine and anaerobic digester filtrate: comparison of adsorption–precipitation with direct precipitation

“…Based on previous reports, the percent P of struvite precipitated in anaerobic digester sidestreams can vary from low to close match with pure struvite. 57 The XRD results for the solid precipitated in the spent regenerant corresponding to anaerobic digester filtrate showed a better match with the major d-spacings and relative intensities for pure struvite than the solid from direct precipitation. S5 in ESI †).…”

“…12,45,52 Additionally, previous reports show that the percent P of struvite precipitated in urine can vary from 7.2-18%. 49,57 The solid precipitated in fresh urine and the spent regenerants corresponding to fresh urine and hydrolyzed urine showed higher P content than pure potassium struvite (see Table 3). S4 in ESI †).…”

“…This suggests that other calcium and magnesium phosphate solid phases precipitated with potassium struvite. 57 In addition, the XRD results suggested the presence of halite in the solid collected from the spent regenerants even though the chemical equilibrium calculations showed halite was undersaturated. 51,52 Additionally, trimagnesium phosphates IJMg 3 IJPO 4 ) 2 ·8H 2 O, 15.22% IJm/m) P; Mg 3 IJPO 4 ) 2 · 22H 2 O, 9.40% IJm/m) P) and magnesium sodium phosphate IJMgNaPO 4 ·7H 2 O, 11.54% IJm/m) P) are known to precipitate with potassium struvite.…”