corundum, synthetic corundum.7, synthetic orange sapphire, Chatham, flux, gems

Gunawardene examines the identification of Chatham flux-grown synthetic orange sapphire, material produced to imitate the orange-pink colour associated with Sri Lankan padparadscha sapphire. The paper documents the material’s gemmological properties and concentrates particularly on microscopic characteristics useful for separating it from natural sapphire. Diagnostic features associated with flux growth include residual flux and characteristic inclusions, together with growth features related to synthetic crystallization. The author also discusses platinum inclusions, derived from the crucibles used during growth, as an important indication of synthetic origin. The study compares these observations with natural orange sapphires and emphasizes microscopic examination as a practical means of identification.