Abstract
Kimberlitic zircons from 16 intrusions in Lesotho, the Republic of South Africa, and Tanzania have been investigated. The following characteristics distinguish the kimberlitic zircons from the zircons derived from most other sources: 1. Rounded to subrounded grains predominate; euhedral zircons are very rare. 2. Perfect parting in several directions, mainly (100) and (111). 3. Lattice distortions occur (decreasing molar volume). 4. High abundancy of fluid inclusions, occupying healed fractures. 5. Uranium contents less than 30 ppm U. Low contents of Th, Y, P, REE. 6. Whitish alteration rims composed of monoclinic and tetragonal zirconia in varying proportions are common. — The use of zircons in order to identify and trace kimberlite intrusives is discussed, as there may be a possible connection between some properties of the kimberlitic zircons and the diamond grade of their host rocks.
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Ahrens, L. H., Cherry, R. D., Erlank, A. J.: Observations on the Th-U relationship in zircons from granitic rocks and from kimberlites. Geochim. Cosmochim. Acta 31, 2379–2387 (1967)
Boyd, F. R., Nixon, P. H.: a) Origin of the ilmenite-silicate nodules in kimberlites from Lesotho and South Africa. In: Lesotho Kimberlites, P. H. Nixon, Ed. LNDC, Maseru, Lesotho pp. 254–268 (1973)
-- -- b) Origin of the lherzolite nodules in the kimberlites of northern Lesotho. Intern. Conf. Kimberlites, Ext. Abstr., Cape Town 47–50 (1973)
-- -- c) Origin of the discrete nodules in the kimberlites of northern Lesotho. Intern. Conf. Kimberlites, Ext. Abstr., Cape Town 51–54 (1973)
Clark, G. L., Reynolds, D. H.: Chemistry of zirconium dioxide. Ind. Eng. Chem. 29, 711–715 (1937)
Cyprès, R., Wollast, R., Raucq, J.: Beitrag zur Kenntnis der polymorphen Umwandlungen des reinen Zirkonoxides. Ber. Deut. Keram. Ges. 40, 527–532 (1963)
Cornelissen, A. K., Verwoerd, W. J.: The Bushmanland kimberlites. Intern. Conf. Kimberlites, Ext. Abstr., Cape Town 71–74 (1973)
Dawson, J. B.: a) A review of the geology of kimberlite. In: Ultramafic and related rocks, pp. 241–251, P. J. Wyllie, Ed. New York: J. Wiley & Sons 1967
— b) Geochemistry and origin of kimberlite. In: Ultramafic and related rocks, 269–278, P. J. Wyllie, Ed. New York: J. Wiley & Sons 1967
Holmes, A.: Contributions to the petrology of kimberlite and its inclusions. Trans. Geol. Soc. S. A. 39, 379–428 (1936)
— Paneth, F. A.: Helium ratios of rocks and minerals from the diamond pipes of South Africa. Proc. Roy. Soc. A 154, 385–413 (1936)
Kable, E. J. D., Fesq, H. W., Gurney, J. J.: The significance of the inter-element relationship of some refractory elements in South African kimberlites. Intern. Conf. Kimberlites, Ext. Abstr., Cape Town 185–188 (1973)
Krauth, A., Meyer, H.: Über Abschreckmodifikationen und ihr Kristallwachstum in Systemen mit Zirkonoxid. Ber. Deut. Keram. Ges. 42, 61–72 (1965)
Kresten, P.: Heavy mineral survey and kimberlite occurrences in the area west of Butha Buthe (Leribe district). Diam. Expl. Proj., Spec. Rep. PK/1. Dept. of Mines, Maseru, Lesotho (1972)
— a) The coating of kimberlitic zircons: A preliminary study. In: Lesotho Kimberlites, pp. 220–223, P. H. Nixon, Ed. LNDC, Maseru, Lesotho (1973)
-- b) Kimberlitic zircons. Intern. Conf. Kimberlites, Ext. Abstr., Cape Town 191–194 (1973)
— Uranium in kimberlites and associated rocks, with special reference to Lesotho occurrences. Lithos, 7, 171–180 (1974)
Longo, V., Podda, L., Roitti, S.: Thermal shock resistance of CeO2-stabilized zirconia; behaviour of the material in the presence and absence of impurities. Sci. Ceram., Vol. 7 (1973)
Meyer, H. O. A., Svisero, D. P.: Mineral inclusions in Brazilian diamonds. Intern. Conf. Kimberlites, Ext. Abstr., Cape Town 225–228 (1973)
Milashev, V. A.: Petrochemistry of the kimberr lites of Yakutia and characteristics of theidiamond mineralization. “Nedra”, Leningrad 1965. Transl. BRGM, Orleans, A. J. A. Janse, Ed., 1969
Mitchell, R. H., Crocket, J. H.: Diamond genesis, a synthesis of opposing views. Min. Depos. 6, 392–403 (1971)
— Carswell, D. A., Brunfelt, A. O.: Mineralogy and Rare Earth geochemistry of an ilmenite — clino-pyroxene xenolith from the Monastery Mine. In: Lesotho Kimberlites, pp. 224–229, P. H. Nixon, Ed. LNDC, Maseru, Lesotho (1973)
— Brunfelt, A. O., Nixon, P. H.: Trace elements in magnesian ilmenites from Lesotho kimberlites. In: Lesotho Kimberlites, pp. 230–235, P. H. Nixon, Ed. LNDC, Maseru, Lesotho (1973)
Modreski, P. J.: The melting of phlogopite in the presence of enstatite, aluminous enstatite, diopside, spinel, corundum, and pyrope. Carnegie Inst. Year Book 71, 392–396 (1972)
Nekrasova, R. A., Gamjanina, V. V.: The composition of rare earth elements in kimberlite minerals. Dokl. Akad. Nauk SSSR 182, 449–452 (1968)
— Rozhdestvenskaya, I. V.: The ZrO2/HfO2 ratio in zircons from kimberlites and alluvial sediments. Geochem. Intern. 7, 536–542 (1970)
Nixon, P. H., Boyd, F. R.: a) The discrete nodule association in kimberlites from northern Lesotho. In: Lesotho Kimberlites, pp. 67–75. P. H. Nixon, Ed. LNDC, Maseru, Lesotho (1973)
— b) Deep seated nodules. In: Lesotho Kimberlites, pp. 106–109, P. H. Nixon, Ed. LNDC, Maseru, Lesotho (1973)
Roedder, E.: Liquid CO2 inclusions in olivine bearing nodules and phenocrysts from basalts. Am. Mineral. 50, 1746–1782 (1965)
Rolfe, D. G.: The geology of the Kao kimberlite pipes. In: Lesotho Kimberlites, pp. 101–106, P. H. Nixon, Ed. LNDC, Maseru, Lesotho (1973)
Strunz, H.: Mineralogische Tabellen. 4. Auflage. Akadem. Verl. Ges., Leipzig 1966
Wagner, P. A.: The diamond fields of southern Africa. Johannesburg: The Transvaal Leader 1914
Whitelock, T. K.: The Monastery Mine kimberlite pipe. In: Lesotho Kimberlites, pp. 214–220, LNDC, Maseru, Lesotho (1973)
Williams, A. F.: The genesis of the diamond. 2 Vols, London: E. Benn Ltd. 1932
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Kresten, P., Fels, P. & Berggren, G. Kimberlitic zircons — A possible aid in prospecting for kimberlites. Mineral. Deposita 10, 47–56 (1975). https://doi.org/10.1007/BF00207460
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DOI: https://doi.org/10.1007/BF00207460