European Journal of Scientific Research (ISSN: 1450 ... - EuroJournals

© European Journal of Scientific Research, Vol 7, No 5, 2005
PIXE MICROANALYSIS OF MUSCOVITE SAMPLES FROM TOURMALINE
BEARING GRANITE PEGMATITES OF SOUTHWESTERN NIGERIA
O. A. Ige a , S.O.Olabanji b , D. Ceccatob c
a
Natural History Museum, Obafemi Awolowo University, Ile-Ife, Nigeria
b
National Institute for Nuclear Physics (INFN), National Laboratories of Legnaro (LNL), Viale
dell’Università 2, 35020 Legnaro Padua, Italy.
c
ICTP – TRIL fellow on sabbatical leave from Centre for Energy Research and Development
(CERD), Obafemi Awolowo University, Ile-Ife, Nigeria.
ABSTRACT
Nearly pure muscovite samples from pegmatite bodies within two different geological
environments have been characterised using an accelerator-based analytical technique of PIXE
and Electronprobe microanalyser, in order to determine their major, minor and trace elements
composition and possible industrial application. 17 elements were measured and result shows that
the muscovites from the two localities are generally similar in composition with extensive
substitution in the K and Al sites. Trace element differences such as Au are interpreted as
reflecting the geological environments.
Key words: Muscovites, PIXE, microprobe,trace element.
INTRODUCTION
The analysis of trace elements in industrial minerals holds the key to understanding ore metal
pathways and ore formation processes. Proton-induced X-ray emission (PIXE) analysis and the
Electron microprobe provide direct non-destructive methods for the determination of the
composition of these trace elements with detection limits down to 20 ppm. Muscovite
(Al1.788KMg.64O12Si3.572), often called white mica, is a rock-forming mineral that has a
layered structure of sheets of aluminum silicate weakly bonded together by layers of potassium
ions. Due to its perfect cleavage, elasticity, and low thermal conductivity, muscovite is often used
for electrical and thermal insulation applications and also as a lubricant. Finely ground muscovite
is sometimes used to make special surfaces in prints and paintings. It was also used in this
fashion as furnace doors, but its use in this capacity is not as common today because of modern
technology alternatives.
Muscovite is a common mineral found all over the world, however most locations do not produce
a high yield product. The largest and most important deposits of muscovite are found in the CIS,
Pakistan, India, and Brazil. The United States produces only a small amount of high yield sheet
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