Feature Gems & Gemology, Fall 1995, Vol. 31, No. 3

“Ti-Sapphire”: Czochralski-Pulled Synthetic Pink Sapphire from Union Carbide

One of the most interesting of the commercially available Czochralski pulled synthetic corundums is pink “Ti-sapphire.” This material owes its pleasant, somewhat orangy pink color to trivalent titanium, a common trace element in natural sapphires and rubies that occurs here in an unusual oxidation state. Although most of the gemological features are typical of Czochralski-pulled corundum (gas bubbles or small "pinpoint” inclusions, color zoning), these synthetic sapphires have distinctive fluorescence and optical spectra. These properties are also due to the chromophore Ti3+.