This raw material study can be assumed as a preliminary stage in the investigation. Struverite-magnetic middling is frequently left behind in substantial quantities. It cannot be upgraded using common process because of the magnetic behavior of some cassiterite. In general, the results of mineralogical investigation indicate that cassiterite contained has already had good liberation. Thus it becomes a positive factor in the physical treatment of the middling. However, in relation to the magnetic behavior, the result indicates that most cassiterite and struverite have the same degree of magnetism which is the main problem in separating the cassiterite. It is expected that the best treatment to upgrade the struverite can be determined and the commercial product will be obtained to increase the economic value in the tin mining industry.