Hopeite


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Related to Hopeite: parahopeite

Hope´ite


n.1.(Min.) A hydrous phosphate of zinc in transparent prismatic crystals.
References in periodicals archive ?
Furthermore, Sample C provided less creepage because of the low solubility of the phosphophyllite structure present in the phosphate coating in a high alkaline medium as opposed to the hopeite structure of Sample D.
The standards selected for Zn were ferrihydrite adsorbed Zn (Zn-[Fe.sub.5][O.sub.3][(OH).sub.9]), franklenite (Zn,[Mn.sup.2+],[Fe.sup.2+]) [([Fe.sup.3+],[Mn.sup.3+]).sub.2][O.sub.4]), hopeite ([Zn.sub.3][(P[O.sub.4]).sub.2].2([H.sub.2]O)), hydrozincite ((Zns[(C[O.sub.3]).sub.2][(OH).sub.6]), scholzite (Ca[Zn.sub.2][(P[O.sub.4]).sub.2].
The calcium-modified crystal is the Scholzite structure Ca[Zn.sub.2] (P[O.sub.4])2 2[H.sub.2]O as compared with Hopeite ([Zn.sub.3] [(P[O.sub.4]).sub.2] 4[H.sub.2]O), the non-calcium zinc phosphate structure.
X-ray diffraction equipment is less apt to be found in the analytical lab of a paint supplier or user, but it commonly is used to identify the different crystalline phosphates produced by the zinc phosphating process, such as hopeite ([Zn.sub.3][([P0.sub.4]).sub.2] * 4[H.sub.2]0) and phosphophyllite ([Zn.sub.2]Fe[([P0.sub.4]).sub.2] * 4[H.sub.2]0).
From Zimbabwe there are two wonderful specimens of kermesite from Que Que, and from Zambia there is a wonderful football-sized specimen of hopeite with large pale yellow crystals.
Many investigators have provided conclusive evidence for the ability of phosphate to immobilise dissolved Pb in contaminated soils through precipitation as fluoropyromorphite, pyromorphite, hydroxypyromorphite, and chloropyromorphite, and as hopeite in the case of Zn (Bolan et al.
In that case, the phosphated layer is essentially composed of hopeite ([Zn.sub.3][(P[O.sub.4]).sub.2], 4[H.sub.2]O) and of phosphophyllite ([Zn.sub.2]Fe[(P[O.sub.4]).sub.2], 4[H.sub.2]O).
(3) The main crystalline components of zinc phosphate layers are hopeite ([Zn.sub.3](P[O.sub.4])2*4[H.sub.2]O and phosphophyllite ([Zn.sub.2]Fe(P[O.sub.4])[.sub.2]*4[H.sub.2]O).
These include sicklerite, purpurite, hureaulite, phosphosiderite, strengite, stewartite, eosphorite, robertsite, mitridatite, jahnsite, fairfieldite, hopeite, and pseudomalachite.
See La Bomba Kami Apatite, arsenopyrite, cassiterite, ferbertite, jarosite, jeromite, lazulite, pyrite, pyrrhotite, quartz twins, scorodite, siderite, tourmaline, wolframite Kari-Kari Almandine, epidote, hopeite; see Andacaba Kentiyok Galena Kesniri Barite, galena, pyromorphite La Bella Beryl, columbite, fergusonite, fluorite, monazite, topaz La Bomba Fluorite, scheelite La Colorada Bournonite, cassiterite, franckeite La Escosasa Galena La Gaiba See Anahi, Ayoreita La Joya Gold, muscovite La Paz La Ponderosa Chalcedony, copper La Reforma Bsimuth, bismuthinite La Salvadora 1 La Salvadora is the name of the (see Socavon) cooperative operating the Socavon.
Hopeite [Zn.sub.3][([PO.sub.4]).sub.2] [center dot] 4[H.sub.2]O