Cubic Zirconia occurs naturally but is very rare. The manufactured material is therefore synthetic and was introduced to the market as a diamond simulant, often referred to as simply 'CZ'. It has impressive gemstone properties including a dispersion level higher than that of diamond and a bright vitreous lustre. Rough material is cheap to purchase and features a wide colour range that is continuously expanding.
Cubic zirconia is often confused with the natural gemstone zircon because of a similar description. Zircon is a silicate (zirconium silicate, ZrSiO4) whereas CZ is an oxide (zirconium dioxide, ZrO2) they are therefore unrelated.
CZ is not normally treated.