It was shown in the results that no significantly difference between the lamellar eutectic structure and chemical composition of the sterling silver alloys preparing by investment and metal mould casting. However, it is clearly seen that the lamellar eutectic structure is transformed partially to a continuous Cu-Si structure when the Si content is increased to 0.05-0.1wt% and it has completely changed to a continuous Cu-Si structure at 0.3wt%.