1.22 Ct. Cabochon Alexandrite from Russia

One translucent oval alexandrite presented by The Natural Gemstone Company, weighing 1.22 carat, measures 7.29 by 5.56 by 3.23 millimeters, and is fashioned as a cabochon. The oval outline is well centered, the dome is proportioned to favor the optical phenomenon without sacrificing surface symmetry, and the overall finish is described as excellent polish. Clarity is graded included at eye level, which indicates visible internal characteristics when examined without magnification, while translucency permits soft light transmission that enhances the color change. Color intensity is evaluated as medium light, giving the stone a balanced appearance that reads as green in daylight and shifts to pink under incandescent illumination. No treatments or enhancements have been applied, and the material is documented as Russian in origin, a provenance that is historically significant for alexandrite and often associated with classical color change specimens.

From an optical and gemological perspective this cabochon demonstrates the characteristic alexandrite color change caused primarily by chromium substitution in the chrysoberyl structure interacting with the spectral distribution of the viewing light source. Under daylight balanced spectrum conditions the stone exhibits green tones, and under warm incandescent illumination the same material reads pink, a transition consistent with a true alexandrite effect. The cut as a cabochon is specifically intended to maximize the perception of that change, the moderate dome height of approximately forty four percent of the length providing sufficient depth for color to integrate while maintaining a pleasing silhouette for jewelry mounting. Internal features are present and account for the included clarity grade, and these natural growth features are commonly encountered in material from Russian deposits. Optical constants for chrysoberyl are informative for mounting and conservation considerations, with a refractive index in the range 1.746 to 1.755, low birefringence, and a specific gravity near 3.72 to 3.84, together with a Mohs hardness of about 8.5 which supports daily wear in well designed settings.

Craftsmanship notes focus on the cabochon faceting and surface preparation, the cutter maintaining a clean domed table to allow a continuous color field rather than distinct light return facets, and achieving a mirror like polish that contributes to the perceived depth and saturation. The oval proportions are optimized for a bezel or closed back mounting which will protect the girdle and emphasize the color change when rotated between light sources. For gem cutters and designers the piece offers predictable orientation behavior, with the visual color change most pronounced when the dome faces the light source and the pavilion curvature controls light leakage. Conservation advice is to avoid abrupt thermal shock and aggressive ultrasonic cleaning if there are surface reaching fissures, preferring warm soapy water and a soft brush for routine maintenance. The combination of Russian origin, no enhancement, documented dimensions, and the intact alexandrite effect make this cabochon a technically interesting specimen for collectors and for designers seeking an authentic color change gem, and The Natural Gemstone Company can provide additional documentation and photography under multiple light sources upon request.