Zirconium oxide is used in some specialist glass formulations to increase the strength and also the refractive index. Lead free crystal glass contains up to 20% zirconium oxide, giving the glass a high refractive index and making it suitable for cutting and engraving.
Borosilicate glass used in LCD’s and plasma display panels often contain up to 1% of zirconium oxide.
Thin film optical coatings are used on windows, mirrors and lens and are advanced multi layer compositions of several materials including zirconium oxide. These thin film coatings are used for abrasion resistance.
Fully stabilised cubic zirconia is used in the production of artificial diamonds used in both industry and jewellery.