the compositions of the investment cast sample are almost the same to that of the metal mould casting but the more relate in chemical composition with respect to nominal composition in the investment cast sample than that produced by metal mould casting. Silver enrichment of the dendritic α-phase are approximately above 90wt%Ag. The dendritic α-phase has same structure but difference in silver concentration due to the formation of coring structure during solidification. Copper are dissolved in the α-phase as a solid solution and small amounts of Zn can be found. The interdendrite region or dendrite edge shows an higher in copper content while the amount of silver was decreased. It should be noted that all the α-phase have the same structure with only difference in concentration gradient due to coring structure. The EDS analysis confirmed a strong enrichment of Cu as a main constituent in the degenerated eutectic structure with a significantly amount of Si. This would be due to the higher solubility of Si in copper than in silver.(8) However, Carbon was presented especially in the Cu-rich phase and tends to decreased when increasing Zn and Si.