Blast fragmentation is a measure of efficiency in an open cast blast operation. Specific Charge (SC) plays an influential role on the fragmentation distribution, the quality of product and the production cost. Dynamic properties of rocks can be used for estimation of rock fragmentation and specific charge. Fragmentation analysis by digital image processing is a low cost and quick method. In this paper, the results of the seismic refraction technique are presented for Choghart Iron ore mine in central Iran. The P-wave velocity of the ore body has been measured at the site. The source of vibration generation was by hammering. The fragmentation resulting from blasting was monitored using a digital camera. Split Desktop software was used to quantify fragmentation size distribution. The mean fragmentation size of P50 was obtained as representative of the average fragmentation size. SC of ANFO was calculated. The relationship between SC with P50, Vp and Dynamic Elasticity Modulus (Edyn) were obtained. It was found that P50 and SC are increased with increased Vp and Edyn. P50, increases with increase of SC. These results can be utilised in blasting design in order to optimise fragmentation and SC for improvement in t the blast operation efficiency.