1.73 Ct. Bi Color / Parti Sapphire from Ceylon (Sri Lanka)

One transparent 1.73 carat oval bi color parti sapphire, dimensions 8.16 x 5.56 x 4.52 mm, presents an exacting combination of proportion and optical performance that makes it exceptionally well suited to custom jewelry. The cutter employed a mixed brilliant faceting scheme, with a precisely faceted crown that promotes strong scintillation, and a carefully controlled pavilion geometry that balances light return with deliberate color zoning. The length to width ratio of about 1.47 yields an elegant oval silhouette that elongates the finger without appearing overly narrow, while the pavilion depth produces an approximate overall depth of 66 percent, an intentional choice to preserve carat weight while avoiding color windowing. Clarity is graded as eye clean at typical viewing distance, enabling unobstructed appreciation of the intense color intensity and the striking bicolor distribution without the need for magnification, and the finish exhibits excellent polish across all facet planes, delivering crisp facet junctions and mirror like reflections.

From a gemological and design perspective this Ceylon sapphire responds beautifully to orientation sensitive settings, because the parti coloration oscillates between saturated golden yellow and deep blue tones with strong pleochroic tendencies. Heat treatment has been applied to stabilize and enhance hue and tone, this treatment is standard practice for Sri Lankan sapphires and yields long term color stability when set and worn under normal conditions. The mixed brilliant cut was executed to emphasize both color zoning and brilliance, enabling the stone to read differently under varying angles of light, a quality that bespoke jewelers can exploit to create dynamic pieces. At 8.16 x 5.56 mm the stone fits standard oval mounting templates for rings, pendants, and earrings, while its slightly elongated outline makes it an excellent focal for three stone designs, halo settings, and east west configurations that deliberately showcase the two color fields. For clients and designers seeking technical predictability, The Natural Sapphire Company provides detailed cutting data and imaging to assist in setting orientation and metal choices, assuring that the chosen mount will maximize optical impact and structural security. This sapphire is therefore an outstanding candidate for custom work where precise proportions, predictable light performance, and dramatic bi color appeal are required.