Silica cat litter is a unique mineral-based litter type composed of amorphous silica gel granules (NOT crystalline silica! More on that later), which are known for their absorbent and lightweight nature. When liquid is exposed to these miniature porous beads, it's pulled into the network of microscopic pores and trapped along with any accompanying odors. Eventually, the water evaporates and leaves the smelly compounds behind; this is what grants crystal litter its odor controlling capabilities.