Ceramic putter head. On front is "Coors" in green near a center mark line on top of putter. On reverse side is "ZrO2" in green, which is the chemical notation for zirconium oxide, also known as zirconia. A hole to insert shaft is offset near center mark line on top of putter. Coors Ceramics Company created a line zirconia-based ceramic products including golf putters and drivers as well as golf cleats