Sponge titanium is the raw material for titanium processing materials. Generally, it is a light gray particle with a clean surface and no visible inclusions. It also includes defective sponge titanium blocks, such as burnt sponge titanium blocks, oxidized sponge titanium blocks with obvious dark yellow and bright yellow traces, oxidized and nitrogen rich sponge titanium blocks with dark yellow and bright yellow traces, sponge titanium blocks with obvious chloride residues, and sponge titanium blocks with residues.Divided into five levels based on purity: WHTiO to MHTi4