Mineralogy phosphates

Pigna M, Colombo C, Violante A (2003) Competitive sorption of arsenate and phosphate on synthetic hematites (in Italian). Proceedings XXI Congress of Societa Italiana Chimica Agraria SICA (Ancona), pp 70-76 Quirk JP (1955) Significance of surface area calculated from water vapour sorption isotherms by use of the B. E. T. equation. Soil Sci 80 423-430 Rancourt DG, Fortin D, Pichler T, Lamarche G (2001) Mineralogical characterization of a natural As-rich hydrous ferric oxide coprecipitate formed by mining hydrothermal fluids and seawater. Am Mineral 86 834-851 Raven K, Jain A, Loeppert, RH (1998) Arsenite and arsenate adsorption on ferrihydrite kinetics, equilibrium, and adsorption envelopes. Environ Sci Technol 32 344-349... 

Total phosphorus content of phosphate rocks is relatively unimportant, since what really matters is its reactivity in the soil, which in turn depends on the soil itself, the rock mineralogy and the level of rock grinding. 

Most minerals occur in a variety of morphologies. Although it is not exhaustive, the list we recorded as occurring in fibrous form (Appendix 1) contains more than 350 entries, each with a reference. The format follows that proposed in Dana s System of Mineralogy, (Palache, et al., 1944), one of the standard references in the field. The names of fibrous minerals are alphabetically arranged within each chemical group that is, elements, oxides, hydroxides, carbonates, sulfates, phosphates, and so on. A similar, parallel system has been adopted for the list of synthetic fibers (Appendix 2). The list of synthetics includes glassy fibers produced from natural materials, as well as whiskers. 

According to a literature survey conducted by Shahalam [28], the contents of various chemicals found in the natural mined phosphate rocks vary widely, depending on location, as shown in Table 1. For instance, the mineralogical and chemical analyses of low-grade hard phosphate from the different mined beds of phosphate rock in the Rusaifa area of Jordan indicate that the phosphates are of three main types carbonate, siliceous, and silicate-carbonate. Phosphate deposits in this area exist in four distinct layers, of which the two deepest - first and second (the thickness of bed is about 3 and 3.5 m, respectively, and depth varies from about 20 to 30 m) - appear to be suitable for a currently cost-effective mining operation. A summary of the data from chemical analyses of the ores is shown in Table 2 [28]. 

Borggaard, O.K. (1983) Effect of surface area and mineralogy of iron oxides on their surface charge and anion-adsorption properties. Clays Clay Min. 31 230-232 Borggaard, O.K. (1983 a) The influence of iron oxides on phosphate adsorption by soil. J. 

J. Electrochem. Soc. 114 994-1000 Fontes, M.P.F. Weed, S.B. (1991) Iron oxides in selected Brazilian oxisols I. Mineralogy. Soil Sd. Soc. Am. J. 55 1143-1149 Fontes, M.P.F. Weed, S.B. (1996) Phosphate adsorption by days from Brazilian oxisols relationships with specific surface area and mineralogy. Geoderma 72 37-51 Fontes, M.P.F. Bowen, L.H. Weed, S.B. 

Phosphate sorption by natural hematites. Eur. J. Soil Sd. 45 45—51 Torrent, J. Schwertmann, U. Schulze, D.G. (1980) Iron oxide mineralogy of some soils of two river terrace sequences in Spain. Geoderma 23 191-208... 

Spectral parameters of the structured green luminescence (Fig. 4.4d) are absolutely similar to those of luminescence in fluorite after thermal treatment (Tarashchan 1978). Principally, during the calcination of the sedimentary phosphates new mineralogical phases, including fluorite, may be formed. Taking these data into accoimt, it is possible to conclude that after thermal treatment uranium is concentrated in the fluorite lattice in the form of... 

Karpoff, A. M., Peterschmitt, I. Hoffert, M. 1980. Mineralogy and Geochemistry of Sedimentary Deposits on Emperor Seamounts, Sites 430, 431 and 432 Authigenesis of Silicates, Phosphates and Ferromanganese Oxides. Initial Reports Deep Sea Drilling Project, LV, US Gov. Print. Office, 463-489. 

Hikichi, Y Murayama, K., Ohsato, H. Nomura, T. 1989. Thermal changes of rare earth phosphate minerals. Journal of the Mineralogical Society of Japan, 19, 117-126. 

PlANTONE, P., BODENAN, F., DERIE, R. Depelsenaire, G. 2003. Monitoring the stabilization of municipal solid waste incineration fly ash by phosphatation mineralogical and balance approach. Waste Management, 23, 225-243. 

Tardy, Y. Veillard, P. 1977. Relationships among Gibbs Free Energies and enthalpies of formation of phosphates, oxides and aqueous ions. Contributions to Mineralogy and Petrology, 63, 75-88. 

Hascman, J.F., Lehr, J.R. and Smith, J.P., 1951. Mineralogical character of some iron and aluminum phosphates containing potassium + ammonium. Proc. Soil Sci. Soc. Am., 15 76-84. 

The listed chemical formulae are ideal and most of these minerals contain trace and minor elements which undoubtedly affect the CL. Several of these minerals have polymorphic or compositional varieties which also may, or do, show CL (e.g. the silica polymorphs quartz, cristobalite, tridymite phosphate compositional varieties apatite, whitlockite, farringtonite, buchwaldite carbonate compositional varieties calcite, dolomite, magnesite). Glass and maskelynite (shock modified feldspar), although not strictly minerals, are relatively common. Below are described the CL observations for the most common phases including enstatite, feldspar and forsterite and they are related to their use for interpreting the mineralogy of meteorites. The observations for the other minerals are sporadic and many details have yet to be studied. 

There are only a few minerals where thorium occurs as a significant constituent. The commercially important ore is the golden-brown, lanthanide phosphate, monazite [13064-1 -8/, LnPO where Ln = Ce, La, or Nd, in which thorium is generally present in a 1—15% elemental composition (7,8). Monazite is widely distributed around the world. Some deposits are quite large. Beach sands from Australia and India contain monazite from which concentrates of lanthanides, titanium, zirconium, and thorium are produced (7). The Travancore deposits in India are the most famous, and have been perhaps one of the most significant sources of commercial thorium. Additional information on the occurrence of thorium in minerals can be found in the literature (7). A review of the mineralogy of thorium is also available (9). 

Van Kauwenberg3 has described the mineralogy and alteration of phosphate ores in Florida. Mineralogical composition varies by particle size. Francolite and then quartz are the most abundant minerals for plus 20-mesh particles (pebble), while the reverse is true for particles in the 20-200-mesh fraction (flotation feed). In the minus 200-mesh size fraction (clay waste) quartz, francolite, wavellite, crandallite, goethite, dolomite, and a variety... 

Naturally occurring phosphate cements are also known. Krajewski [3] cites calcium-based phosphate cements in the Albeian condensed Glauconitic Limestone of the Tatra Mountains in Western Carpathians. In recent years methods have been developed to fabricate calcium phosphate ceramics by direct reaction of calcium compounds and either phosphoric acid or an acid phosphate. The mineralogy of the products has also been well studied. Most of these efforts are directed towards development of calcium-based bioceramics containing calcium phosphate compounds, such as hydroxyapatite. These developments are discussed below. 

---