Investment vacuum mixing is important part in jewellery making machinery unit. Generally investment vacuum mixer design is different in silver casting machine or gold casting machine or platinum casting machine, or metal casting machine. And high precision control requirement in vacuum assisted auto pouring vacuum casting machine or say bottom pouring vacuum casting machine. There are two designs for investment mixer. One attached with bottom pouring vacuum pressure Casting machine & second is single Investment vacuum mixer. Investment vacuum Mixer or Investment Vacuum Machine design is different in Centrifugal casting machine. The result of gold or silver jewellery depends on quality of Investment powder for gold casting, or silver casting also. Lost wax casting process result achieved with Investment casting machine has importance of vacuum and vibration process. Wax tree placed in investment vacuum machine and flasks are filled with investment powder in vacuum atmosphere and vibration effect provides better wax surface and so as silver casting surface & gold casting surface. Investment vacuum mixing process is important in Lost wax casting process.