...Fabrice Brunet; Torsten Schaller Abstract Two structurally related magnesium phosphates, phosphoellenbergerite ( P 6 3 mc ) and holtedahlite ( P 6 3 ), have been investigated using a combination of high-frequency IR and 1 H MAS, 31 P MAS, and 31 P CP MAS NMR spectroscopy on synthetic material...

... occupied, and only very weak hydrogen bonds exist. Satterlyite is isostructural with holtedahlite, Mg 12 (PO 3 OH,CO 3 )(PO 4 ) 5 (OH,O) 6 . Unlike in natural holtedahlite, there is no carbonate-for-phosphate substitution in the satterlyite investigated, which was also confirmed by IR absorption powder...

...(4) Å, β = 108.38(4)°, V = 1396.2(8) Å 3 , Z = 16, i.e. , hydroxylwagnerite is the OH-dominant analogue of wagnerite [β-Mg 2 PO 4 (OH)] and a high-pressure polymorph of althausite, holtedahlite, and α- and ε-Mg 2 PO 4 (OH). We suggest that the group of minerals related to wagnerite, triplite...

...Fig. 13 The (A) ellenbergerite and (B) satterlyite-holtedahlite structures (viewed down their respective c- axes) contain triangular channels formed by bundles of three M H double-chains of octahedra. Dashed lines show how each structure (left) can be assembled from hexagonal supertiles...

...Fig. 6. The crystal structure of holtedahlite: a dense packing of II-rods known from the ekatite and the phosphoellenbergerite structures. The ordering of M(1) cations of holtedahlite is given as M(1.1) and M(1.2). Note that only one half of the X(1) polyhedra of ekatite occurs in holtedahlite...

...Fig. 1. Petrographic thin section showing three crystals of raadeite (arrows) included in holtedahlite and used for complete characterisation of the new species (photomicrograph, crossed nicols). The inclusion in the upper right corner consists of two crystals (medium and dark grey...

...Figure 4 Synchrotron X-ray diffraction. ( a ) Observed and modeled patterns of the red-colored ferric Fe/Mg-merrillite sample along with the residual of the fit. Beyond the expected whitlockite/merrillite observed in the crystal, monetite and holtedahlite also appear to be present. ( b ) Similar...

... be positioned at the center of one or more of the four faces of a PO 4 tetrahedron as observed in holtedahlite ( Rømming and Raade 1989 ). The very low refined occupancy for the P2 site noted above indicates that most of the CO 3 in the structure probably occurs in the vicinity of this site. The small amount...

... with holtedahlite. The fact that anduoite occurs in the löllingite group is missing. The reference to admontite ( Am. Mineral. 65 , 205) does not include the errata in 65 , 1311. The structure reference to aerinite should be “ 84 , 1467” instead of “ 84 , 1464–1468”, as the abstract is only one paragraph...

...) 6.07 (AsO 3 ) 6.06 [(AsO 3 ) 1.52 (HOSiO 3 ) 0.62 ] ∑2.14 . Relationship to other species : Structurally related to phosphoellenbergerite, ellenbergerite and holtedahlite. Name : After Dieter Ekat (1935–1996), a Namibian mining engineer and former owner of the Rubicon mine, Namibia...

... in a spinel lherzolite xenolith from Yemen . Chem. Geol ., 176 , 71 – 72 . Brunet , F. & Schaller , T. ( 1996 ): Protons in the magnesium phosphates phosphoellenbergerite and holtedahlite: An IR and NMR study . Am. Mineral ., 81 , 385 – 394 . Brunet , F. , Bonneau , V...