10.00 Ct. Yellowish Green Prasiolite from Brazil

This 10.00 carat prasiolite from Brazil measures 15.34 x 10.05 x 8.85 mm and is presented in a classic emerald cut that emphasizes axial symmetry and planar facet geometry. The material is a transparent, yellowish green quartz with a refractive index in the quartz range, specific gravity consistent with crystalline silica, and a Mohs hardness that makes it robust for everyday wear. The cutter has respected the stone mass to yield an elongated table and balanced pavilion depth that preserve weight without sacrificing optical performance. The clarity is graded as very very slightly included at eye level, which means that inclusions are minimal and do not disrupt light transmission. The intense color intensity is evenly distributed across the crown and pavilion, and the documented enhancement is heat treatment, a controlled thermal process that stabilizes and intensifies this particular green hue. The combination of size, shape, and even saturation produces a physical presence that reads larger than its carat weight might suggest because of the optimal length to width ratio and the generous depth.

The emerald cut faceting on this prasiolite is the primary reason the gem exhibits a distinctive and controlled scintillation that differs from brilliant cuts. Rather than a profusion of small pinpoint flashes, the step facets create broad, mirror like flashes and a classic hall of mirrors effect, which is amplified by the stone s excellent polish and precise facet junctions. Because quartz has a modest refractive index and low dispersion, the visual performance leans toward contrast and luster rather than spectral fire. This prasiolite s cutter has compensated for material optical limits by calibrating crown height and pavilion angles to maximize internal reflections within quartz s critical angle, producing strong light return and defined facet boundaries. The result is an intense, penetrating green that shifts subtly with viewing angle, presenting alternating bands of bright and deep tones that highlight the stone s internal clarity. The very very slightly included clarity grade contributes to the sparkle by allowing clean reflection planes, without disruptive inclusions to interrupt the step facet pattern, and the excellent polish ensures that micro surface irregularities do not scatter light.

From a craftsmanship perspective this piece is exemplary of the standards upheld by The Natural Gemstone Company, and the cut proportions and facet architecture are engineered to make the most of prasiolite s crystalline structure. The octagonal outline with canted corners characteristic of emerald cuts delivers controlled brilliance and a spacious table for viewing the gem s internal color, while the symmetric girdle and evenly matched facets ensure consistent return across the stone s surface. Heat treatment has been applied to stabilize and enhance the yellowish green hue, a common and accepted practice for prasiolite that yields a permanent, evenly saturated color when done under controlled conditions. On the finger the gem exhibits commanding presence, with large reflective planes that produce broad flashes in ambient light and crisp reflections under spot illumination, a behavior that gives this prasiolite an appearance of depth and vitality unmatched by many other green gemstones of similar weight. For connoisseurs and technical buyers who value precise faceting, balanced optical engineering, and traceable origin, this Brazilian prasiolite represents a refined synthesis of material quality and lapidary expertise, and our team at The Natural Gemstone Company is available to provide additional measurements, facet maps, and viewing recommendations to fully appreciate its optical performance.