11.20 ct Ceylon Natural Blue Geuda Sapphire Rough from Kataragama Sri Lanka – Unheated Fine Facet Grade

Stone Identity & Quality

This is an 11.20 ct Facet Grade Ceylon Natural Blue Geuda Sapphire rough measuring 11.5 × 14 × 9.8 mm. The stone is from Kataragama village around mining in Sri Lanka and remains in its currently unheated condition.

The rough shows a highly vitreous, glassy-looking body with strong natural luster, visible crystal growth marks, useful depth, and good transparency. It is presented as very fine facet-grade sapphire rough with both cutting interest and possible professional heat-treatment evaluation potential.

Color & Visual Characteristics

The stone shows a light to medium blue appearance through different areas of the body, with the color becoming more visible when strong light passes through the rough.

Its glassy transparency and vitreous surface luster make the internal body relatively easy to study under directed light. Depending on orientation and thickness, the blue can appear stronger in some directions and softer in others.

Because the sapphire remains rough, the final face-up color after cutting will depend on orientation, finished depth, pavilion placement, surface removal, and the internal color distribution.

Internal & External Features

The sapphire shows visible natural crystal growth marks and structural lines across parts of its surface. These features are connected with the original crystal formation and help preserve the natural character of the rough.

The internal body appears transparent and glassy in several areas, while natural inclusions and localized internal features can also be observed. Before any cutting or heating decision, the stone should be examined under magnification and directional lighting to understand:

Color concentration

Transparency

Inclusion position

Silk or geuda structure

Usable depth

Surface-reaching features

Best cutting orientation

Cutting, Specimen, or Treatment Potential

This stone is presented as very fine facet-grade rough, so it can be considered for professional cutting evaluation in its current unheated state.

At the same time, its glassy geuda-type body and blue character may make it interesting for professional heat-treatment evaluation with the possible goal of developing a stronger blue color.

However, sapphire heating is never guaranteed. Even experienced specialists cannot promise the exact final color, clarity, saturation, or treatment response before the process. The reaction depends on the stone’s chemistry, trace elements, internal silk, inclusions, atmosphere, temperature, and heating duration.

For that reason, the decision between keeping the stone unheated, cutting it naturally, or evaluating it for heating should be made only after careful professional inspection.

Source & Ethical Position

This sapphire was sourced from Kataragama village around mining in Sri Lanka through Danushka Gems & Minings’ source-connected gemstone work.

Our approach is to present natural rough sapphire realistically, including both its visible strengths and its uncertainties. We do not guarantee cutting yield, heat-treatment results, final color, or clarity before the relevant process is completed.

This gives gem cutters, heat-treatment specialists, dealers, collectors, jewelers, and international buyers a clearer understanding of the natural material before making a decision.