1.77 Ct. Greenish Blue Cabochon Sapphire from Montana

This specimen is a 1.77 carat, round shape, greenish blue sapphire, presented as a cabochon, with exact dimensions of 6.61 by 6.64 by 3.70 millimeters. The cut is a classical convex cabochon, with a relatively high dome given the depth figure, producing a dome to diameter ratio of approximately fifty six percent, a proportion that emphasizes body color and translucency rather than faceted brilliance. The material is semi translucent, allowing diffuse light transmission through the dome and creating a soft internal glow, rather than windowing or mirror like reflections seen in transparent, faceted stones. The overall hue reads dominantly greenish blue with an intense color intensity, a saturation that remains consistent across the dome under direct viewing, and subtle tone depth that contributes to a pleasing, evenly distributed visual weight in jewelry applications. As photographed and in hand, the surface presents a uniformly rounded profile with no facet planes, focusing attention on color, internal character, and surface finish.

Clarity for this sapphire is graded slightly included, evaluated at eye level, and the stone exhibits internal features typical of Montana origin material, namely natural mineral inclusions and modest growth zoning that influence light diffusion and texture. These internal characteristics are relatively fine in scale, they do not overly interrupt the color field, and they assist in producing the semi translucent appearance that many collectors and designers seek for cabochon pieces. The specimen has been heat treated, an accepted enhancement used to stabilize and intensify hue and to reduce the visual impact of certain inclusions, the result here being a more saturated greenish blue and improved homogeneity of tone. The lapidary finish is described as excellent polish, with a smooth, high luster surface produced by careful successive abrasives and final polishing agents, yielding crisp highlights on the dome and minimal surface blemishes. The cabochon cutter appears to have centered the dome axis effectively, preserving symmetry between the table footprint and pavilion curve, which is essential for balanced light transmission and optimal seating in a bezel or prong cup.

From a setting and design perspective, this sapphire’s dimensions and cabochon profile recommend mounting approaches that protect the perimeter while showcasing the dome. A low to medium bezel that follows the rounded girdle will provide maximum security and highlight the stone’s uniform color field, whereas a flush or channel setting could be used in multi stone layouts where depth must be controlled. The 3.70 millimeter thickness requires a setting seat that accommodates the dome height without creating undue stress points, therefore plan for a seat depth slightly greater than the measured depth to allow for any adhesive or retipping, and confirm bezel wall clearance to prevent edge fracture during assembly. The semi translucent nature and intense color respond well to open back settings when additional light saturation is desired, however given the inclusion content and heat treatment history, a closed back or partially closed back design will protect the stone and maintain a consistent visual depth. In terms of wear, the heat treated sapphire is stable under normal jewelry use, and typical cleaning with warm soapy water and a soft brush is recommended, while aggressive ultrasonic or steam cleaning should be avoided if the piece is heavily included or mounted in a manner that traps cleaning fluids, therefore inspect settings regularly for security and any sign of ingress.

Provenance and provenance related characteristics are part of the appeal for many buyers, and this sapphire originates in Montana, a locality known for producing sapphires with distinctive blue green tones and characterful internal textures, qualities that are appreciated by connoisseurs and designers seeking natural personality rather than eye clean laboratory aesthetics. The Natural Sapphire Company presents this cabochon as a versatile material for bespoke jewelry, offering a balance of intense natural color, conservatively graded clarity, and a high quality lapidary finish, making it suitable for rings, pendants, and artisan settings where the dome form and organic color are the primary design drivers. For technical inquiries about mounting tolerances, complimentary additional imaging, or to request a laboratory report or light transmission assessment, please contact The Natural Sapphire Company directly, and we will provide precise measurements and handling recommendations to integrate this 1.77 carat Montana cabochon into your design with confidence.