Cathodoluminescence minerals

All of the Type A and B inclusions studied are surrounded by a layered rim sequence of complex mineralogy [21] which clearly defines the inclusion-matrix boundary. Secondary alteration phases (grossular and nepheline, especially) are also a common feature of these inclusions, suggesting that vapor phase reactions with a relatively cool nebula occurred after formation of inclusions. Anorthite, in particular, is usually one of the most heavily altered phases the relationship between Mg isotopic composition and alteration is discussed below. (See [12] for striking cathodoluminesce photographs of typical Allende alteration mineralogy.) Inclusion Al 3510 does not fit the normal pattern as it has no Wark-rim and does not contain the usual array of secondary minerals. 

Cathodoluminescence activates electrons in the mineral, which then emit characteristic light rays of distinct wavelengths that can be collected with the CL system. CL imaging is used to... 

A luminescent mineral is a sohd, which converts certain types of energy into electromagnetic radiation over and above thermal radiation. The electromagnetic radiation emitted by a luminescent mineral is usually in the visible range, but can also occur in the ultraviolet (UV) or infrared (IR) range. It is possible to excite the luminescence of minerals by UV and visible radiation (photoluminescence), by a beam of energetic electrons (cathodoluminescence), by X-rays (X-ray excited luminescence) and so on. A special case is so-called thermoluminescence, which is stimulation by the heating of luminescence, prehminary excited in a different way. 

By far the most important activators in mineral luminescence are the iron group ions which exhibit transitions between partly filled d-orbitals. These will dominate the discussion that follows. Luminescence arising from the trivalent rare earth ions occurs in some phosphate minerals but is dealt with elsewhere in this volume (Wright). The filled d-shell ions are activators for cathodoluminescence phosphors such as ZnS, however, most sulfide mineral phases contain too many luminescence poisons for the transitions from these ions to be observed. 

Cathodoluminescence observations by themselves reveal details of texture among minerals and suggest chemical or structural variation within individual grains. Seldom can the CL observations be interpreted without additional information such as chemical or structural analysis. With this in mind, data obtained from the electron microprobe (EMP), ion microprobe (IMP), scanning electron microscope (SEM), or by thermoluminescence studies complement CL observations and many of the CL examples for meteorites can be best interpreted or related to mineralogy through these data. 

During this century there has been considerable interest in the application of thermoluminescence studies to the recent history of meteorites. Natural TL provides a means of exploring radiation history and thermal environment in a manner which is complementary to isotopic methods, and the measurement of natural TL is now routine for the numerous meteorites being returned each year from the Antarctic (3,4). However, induced TL measurements have also proved of considerable interest, because the measurements have implications for the earliest history of meteorites. Essentially, the induced TL properties of meteorites are determined, with a few notable exceptions, by the amount and the nature of the feldspar in them, and feldspar is very sensitive to the major processes experienced by meteorites. In the present paper, we describe our recent work on the induced TL properties of meteorites and briefly discuss how these data relate to early meteorite history. We emphasize the relationship between the TL data and mineral properties. We also present here detailed descriptions of the cathodoluminescence properties of primitive meteorites, as these provide new insights into mineralogical controls on TL properties. 

Harte B., Fitzsimons I. C. W., Harris J. W., and Otter M. L. (1999a) Carbon isotope ratios and nitrogen abundances in relation to cathodoluminescence characteristics for some diamonds from the Kaapvaal Province S. Africa. Mineral. Mag. 63(6), 829-856. 

Rowan, E. L., 1986, Cathodoluminescent zonation in hydrothermal dolomite cements Relationship to Mississippi VaUey-type Pb-Zn mineralization in southern Missouri and northern Arkansas. in Hagi, R. D., ed.. Process Mineralogy VI, Metallurgical Society, p. 69-87. 

Voss, R. L., and Hagni, R. D., 1985, The application of cathodoluminescence microscopy to the study of sparry dolomite from the Viburnum Trend, southeast Missouri in Hausen, D. M., and Kopp, O. C., eds.. Mineralogy Applications to the minerals industry proceedings of the Paul F. Kerr memorial symposium New York, NY, United States, p. 51-68. 

Standard petrographical and mineralogical techniques, including optical and cathodoluminescence (CL) microscopy. X-ray diffraction (XRD) and electron microprobe analysis (EPMA), were used to characterize detrital and diagenetic minerals and textural relationships. Thin sections were half stained with K-Fe cyanide for rapid identification... 

Rey C, Collins B, Goehl T, Dickson IR, Glimcher MJ (1989) The carbonate enviromnent in bone mineral A resolution-enhanced Fourier transform infrared spectroscopy study. Calcif Tissue Inti 45 157-164 Roeder PL, MacArthur D, Ma XP, Palmer GR (1987) Cathodoluminescence and microprobe study of rare-earth elements in apatites. Am Mineral 72 801-811 Ronsbo JG (1989) Coupled substitution involving REEs and Na and Si in apatites in alkaline rocks from the Illimaussaq intmsions. South Greenland, and the petrological implications. Am Mineral 74 896-901 Rouse RC, Dunn PJ (1982) A contribution to the crystal chemistry of ellestadite and the sihcate srrlfate apatites. Am Mineral 67 90-96... 

Kempe U, Gotze J (2002) Cathodoluminescence (CL) behayiour and crystal chemistry of apatite from rare-metal deposits. Mineral Mag 66 151-172... 

Marshall DJ (1988) Cathodoluminescence of Geological Materials. Unwin Hyman, Boston McLean FC, Bundy AM (1964) Radiation, Isotopes, and Bone. Academic Press, New York McLeiman SM (1989) Rare earth elements in sedimentary rocks Influence of provenance and sedimentary processes. Rev Mineral 21 169-200... 

Al-Khalifa IJM, James K, Duirani SA, Khalifa MS (1988) Radiation damage studies of mineral apatite, using fission traeks and thermoluminesoenee techniques. Nucl Tracks Rad Measure 15 61-64 Barbarand J, Pagel M (2001) Cathodoluminescence study of apatite crystals. Am Mineral 86 473-484 Baumer A, Lapraz D, Klee WE (1987) Thermoluminescent properties of hydrothermally prepared apatites. Neues Jahrb Mineral Mon 1987 43-48... 

Gorobets BS (1981) Luminescence Spectra of Minerals, (in Russian) Moscow. 153 p Gotze J, Heimaim RB, Hildebrandt H, Gburek U (2001) Micro structural investigation into calcium phosphate biominerals by spatially resolved cathodoluminescence. Mater Wissen Werkstofflechnik 32 130-136... 

Mariano AN (1988) Some further geological applications of cathodoluminescence. In Cathodoluminescence of Geological Materials. Marshall D J (ed) Unwin Hyman, Boston Mariano AN (1989) Cathodoluminescence emission spectra of REE activators in minerals. Rev Mineral 21 339-348... 

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