2014111 ensp 0183 enspScanning Electron Microscopic image of dark iron flakes when starting material of quantity a 5g is milled for 4hrs b 5g is milled for 8 hrs and c 30g is mill ed for 8hrs and d graph showing the effect of mil ling time and the amount of starting material used 5g and 30g with s imilar ball to powder weight ratio on the mean fla ke