1.16 Ct. Chrysoberyl from Tanzania

This 1.16 carat cushion shape chrysoberyl from Tanzania is a study in precise gemological proportions and disciplined craftsmanship, presenting dimensions of 6.60 by 5.62 by 3.65 millimeters. The cutter elected a mixed brilliant faceting scheme, combining a brilliant style crown with a pavilion that balances brilliant and step elements, to maximize return of light within the stone s high refractive context. The measured depth of 3.65 millimeters yields an overall depth ratio of approximately 59.7 percent relative to the average of length and width, a proportion that favors balanced face up spread while preserving weight and table real estate for scintillation. The color is described as greenish yellow with intense color intensity, showing concentrated chroma across the pavilion while maintaining a lively face up tone. Clarity is graded as very slightly included at eye level, indicating minor internal features that do not detract from transparency or optical performance when set. The polish is excellent, which ensures crisp facet junctions and minimal light scatter at the surface. The gem is natural with no enhancement, and its documented origin is Tanzania, a provenance that corresponds with known beryllium rich environments within the region. The Natural Gemstone Company stands behind the identification details and the absence of treatments.

To appreciate the story encoded in this crystal one must consider the geological theater in which chrysoberyl forms, a process that unfolds over millions of years. Deep in the continental crust, during episodes of regional metamorphism and late stage pegmatitic activity, beryllium mobile in hot aqueous fluids concentrates in structural traps and fractures. Those fluids, enriched with aluminum and moderated by changing temperature and pressure, provide the chemical environment necessary for BeAl2O4 to nucleate and grow. In the Tanzanian belts where this specimen originated, ancient mountain building cycles produced metamorphic host rocks and the introduction of pegmatitic intrusions that acted as chemical reactors. Slow cooling, repeated pulses of fluid flow, and the presence of trace transition metals allowed individual chrysoberyl crystals to achieve transparency and gem quality. The greenish yellow hue of this example is attributable to the absorption characteristics imparted by trace iron and related elements within the crystal lattice, producing selective absorption in the blue and red regions of the spectrum and yielding the observed hue. Over geological time the crystals detached from their growth environment through erosion and transport, eventually being liberated into alluvial concentrations or preserved within residual pockets, where modern lapidary recovery allowed a cutter to select a crystal exhibiting excellent potential for faceting without the need for enhancement.

From a lapidary and sales perspective the decision to present this stone as a mixed brilliant cushion reflects an intent to reconcile optical physics with market preferences. Chrysoberyl s relatively high hardness, near 8.5 on the Mohs scale, permits the creation of well defined facet planes and crisp edges, and the cutter exploited that trait to execute tight facet geometry that promotes high contrast facets and lively scintillation. The mixed brilliant arrangement places a finely faceted crown above a pavilion that is calculated to return critical rays of light to the viewer s eye, compensating for chrysoberyl s modest dispersion by maximizing scintillation and contrast rather than relying on fire alone. The very slightly included clarity grade signals that inclusions are minimal and stable, unlikely to compromise setting or wear, and the excellent polish enhances apparent luster while minimizing surface abrasion that could dull the stone over time. No enhancement has been applied, so color and clarity are intrinsic, offering long term stability and predictable behavior under mounting and daily wear. For collectors and connoisseurs seeking a gemstone with geological pedigree and technical refinement, this 1.16 carat greenish yellow cushion chrysoberyl is a compelling option. The Natural Gemstone Company can provide additional high resolution imagery, facet map documentation, and setting recommendations to ensure the gem is mounted to preserve its optical performance and to suit the intended jewelry application.