Characteristics: Hard, lustrous, grayish, crystalline scales or gray amorphous powder. Soluble in hot, very concentrated acids. Insoluble in water and cold acids. Corrosion-resistant; low neutron absorption. Low toxicity.
Hazards: A suspected carcinogen. Not permitted in cosmetics (FDA). Flammable and explosive as dust or powder, and in form of borings, shavings, etc. Tolerance, (as Zr): 5 mg/m3 of air (applies to all Zr compounds). Powder should be kept in wet storage and protective clothing should be worn.