...Karrie-Ann Kubatko; Peter C. Burns Abstract Oursinite is a rare Co-bearing uranyl silicate of the uranophane group. The structure of oursinite, (Co 0.8 Mg 0.2 )[(UO 2 )(SiO 3 OH)] 2 (H 2 O) 6 , is orthorhombic, space group Cmca , a = 7.0494(5), b = 17.550(1), c = 12.734(1) Å, V = 1575.4(2) Å 3...

... phosphate tetrahedra to form infinite sheets. This sheet-type is identical to the anion topology of the uranophane group, in particular to that of oursinite, Co[(UO 2 )(SiO 3 OH)] 2 (H 2 O) 6 . Similarities between Ba(NpO 2 )(PO 4 )(H 2 O) and the uranophane group of minerals suggests a charge-balancing...

... or uraninite), their physical properties ( e.g . barite, euclase, orthoclase, periclase or scorodite), their use ( e.g . fluorite, graphite, muscovite, pyrite or pyrolusite), similarity to biological objects ( e.g . garnet, malachite or oursinite) or some of their structural features ( e.g . clinoen-statite...

... ) [6] Cu 2+ [(UO 2 )SiO 3 OH] 2 (H 2 O) 6 1.50 5 2 3 6 Sklodowskite ( Ryan and Rosenzweig 1977 ) [6] Mg[(UO 2 )(SiO 3 OH)] 2 (H 2 O) 6 1.50 5 2 3 6 Oursinite ( Kubatko and Burns 2006 ) [6] (Co 0.8 Mg 0.2 )[(UO 2 )(SiO 3 OH)] 2 (H 2 O) 6 1.50 5 2 3 6 Haiweeite (struct...

.... & Burns , P.C. ( 2006 ): A novel arrangement of silicate tetrahedra in the uranyl silicate sheet of oursinite, (Co 0.8 Mg 0.2 )[(UO 2 )(SiO 3 OH)] 2 (H 2 O) 6 . Am. Mineral., 91 , 333 – 336 . Lussier , A.J. , Lopez , R.A.K. , Burns , P.C. ( 2016 ): A revised...

... (12) CoSO 4 ·6H 2 O Effluoresces with S 1,2,3,9,11,14, 29 54 Neustädtelite (4) Bi 2 Fe 3+ (Fe 3+ ,Co) 2 (AsO 4 ) 2 (O,OH) 4 Oxidized ore 2 ,22 55 Oursinite (1) Co(UO 2 ) 2 (SiO 3 OH) 2 ·6H 2 O Secondary mineral 5 56 Pakhomovskyite (1) Co 3 (PO 4 ) 2 ·8H 2 O Carbonatite...

... fuel. Of the fourteen uranyl silicate minerals, nine have a U:Si ratio of 1:1; these are α-uranophane, β-urano-phane, boltwoodite, kasolite, sklodowskite, cuprosklodowskite, oursinite, sodium boltwoodite, and swamboite. The structures are known for six of these; each contains sheets of edge...

... Republic of Congo, by Deliens & Piret (1982) . It is associated with lepersonnite, sklodowskite, curite, uranophane, becquerelite, rutherfordine, studtite, and oursinite. Deliens & Piret (1982) reported that bijvoetite-(Y) is orthorhombic, space groups C 2 ma , Cm 2 b , or Cmma , a 21.223(3...

... – 209 . Kubatko , K.A. & Burns , P.C. ( 2006 ): A novel arrangement of silicate tetrahedra in the uranyl silicate sheet of oursinite, (Co 0.8 Mg 0.2 ) [(UO 2 )(SiO 3 OH)] 2 (H 2 O) 6 . Am. Mineral. , 91 , 333 – 336 . Locock , A.J. , Burns , P.C. , Flynn , T.M...

... on the orientation of the apical, non-bridging, O or OH groups of the silicate tetrahedra. The structure of oursinite, which was only recently reported, represents a new graphical isomer. With the exception of kasolite, all of the uranophane-group minerals with known structures contain acid silicate groups, where...

... this ratio contain sheets (Stohl & Smith, 1981 ; Burns, 2005 ; Grenthe et al. , 2006 ). Nine uranyl silicate minerals (uranophane-α and -β, sklodowskite, cuprosklodowskite, boltwoodite, sodium boltwoodite, kasolite, oursinite and swamboite) have been classified as members of the uranophane group...

..., boltwoodite, curposklowdoskite, sklodowskite, oursinite, kasolite), the tetrahedron contains an (OH) group as the apical anion, except in the case of kasolite. The H-bond network was resolved for oursinite, [(Co 0.8 Mg 0.2 )[(UO 2 )(SiO 3 OH)] 2 (H 2 O) 6 ] by Kubatko & Burns (2006c) , who proposed...

... are the most common U 6+ minerals (Fig. 14 ), though almost 20 other uranyl silicates are known, as tabulated by Finch and Murakami (1999) . They observe that uranosilite [(UO 2 )Si 7 O 15 ] forms only in “highly oxidizing environments,” whereas oursinite [Co(UO 2 ) 2 (SiO 3 OH) 2 ·6H 2 O] forms from...