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Pewter filled seashells were used as coinage in Central India from 500 BC to 11th CE when seashells or cowry were common numismatic until 17th-18th CE in all the continents. The present paper is based on examining of three pewter-filled cowry coins collected from the central Indian state of Madhya Pradesh. The analytical investigations were performed through the ED-XRF, XRD, and SEM-EDX analysis of the coins. The X-ray elemental mapping for the coin surface, as well as the cross-sectional area, was carried to understand the composition of the pewter. Scanning electron microscope coupled with energy-dispersive X-ray analysis was used to study the surface topography and microstructure/inhomogeneity within the coins matrix, and elemental composition was recorded. ED-XRF revealed a concentration gradient on the coin surface to that of composition in bulk. The mineralization of lead, tin, copper, and iron was observed on the coin surface through XRD analysis. Investigations showed the presence of a high concentration of impurities of Fe, Zn, Cu and Sb in the coin matrix due to imperfect metallurgical process. The formation of the tin island in the matrix of the coin was recorded from the cross-sectional analysis due to the improper mixing of component materials and the separation of different phases during solidification. [ABSTRACT FROM AUTHOR]