Facet Grade Ceylon Natural Unheated Kowangu Yellow Sapphire Rough – 14.46 ct from Bibilegama, Sri Lanka

Stone Identity & Quality

This gemstone is a 14.46 ct Ceylon natural unheated Kowangu yellow sapphire rough measuring 16.1 × 9.8 × 8.8 mm. It was sourced from Bibilegama village around mining in Sri Lanka and has an alluvial river-mining form. The stone is described as clean and facet grade, making it suitable for lapidary study, cutting evaluation, and possible professional heating consideration. Its current treatment status is unheated.

Color & Visual Characteristics

The stone shows a yellow body color with a soft natural appearance in rough form. Because it is still uncut, the final face-up color will depend on cutting orientation, depth, polishing, and any future treatment decisions. Kowangu-type yellow sapphire rough is often evaluated for its possible ability to develop stronger yellow or orangy-yellow tones after professional sapphire heat treatment, but the result must be assessed realistically and cannot be guaranteed before heating.

Internal & External Features

Externally, this stone has a natural alluvial surface shaped through river-mining movement before recovery. The rough form appears clean based on the supplied details, with enough body and depth for cutting evaluation. As with all sapphire rough, internal clarity direction, color concentration, surface marks, and usable depth should be checked carefully under proper light before pre-forming or faceting.

Cutting, Specimen, or Treatment Potential

This is facet grade rough, so the main interest is cutting and treatment evaluation. The alluvial shape may support practical cutting planning, but the final shape and yield depend on the cutter’s inspection. Because this is Kowangu yellow sapphire rough, it may also be considered for standard professional sapphire heat treatment to improve color toward vivid yellow or vivid orangy-yellow. However, no heating result should be promised before treatment, because each natural sapphire responds differently. Proper evaluation, experienced handling, and realistic planning are important.

Source & Ethical Position

This Kowangu yellow sapphire rough was sourced from Bibilegama village around mining in Sri Lanka through Danushka Gems & Minings’ source-connected gemstone work. Our approach focuses on honest rough presentation, clear origin information, realistic cutting and treatment guidance, and direct communication with gem cutters, dealers, collectors, and buyers. Each stone is presented with practical details so buyers can understand both the beauty and the technical decisions involved.