2. Bond F. Methods of determining the index Bond ball mill Denver (USA), 1961. - 8. 3. K.J. Olatunji* and A.G. Durojaiye Determination of Bond index of Birnin- Gwari Iron Ore in Nigeria Journal of Minerals & Materials Characterization & Engineering, Vol. 9, No.7, pp.635-642, 2010 jmmce.org Printed in the USA.