Hafnium(IV) Oxide, also known as hafnia or hafnium dioxide (HfO₂), is a high-purity ceramic compound offered here with a 99% purity and a coarse 6-mesh particle size. https://www.noahchemicals.com/product/hafnium-iv-oxide-99-9-pure-tablets-hafniumdioxide-hafnia-hfo%e2%82%82/