0.62 Ct. Aquamarine from Mozambique

This listing presents a transparent 0.62 carat round aquamarine, dimensions 5.71 by 5.71 by 4.02 millimeters, cut in a mixed brilliant configuration, clarity graded very slightly included at eye level, light color intensity, excellent polish, heat treated, and sourced from Mozambique. The mixed brilliant cut blends a brilliant crown geometry with a pavilion that employs modified step elements, yielding balanced return of white light and controlled color saturation. The table and crown facets are calibrated to maximize face up brilliance while the pavilion geometry is tuned to retain color depth in a relatively shallow diameter. The Natural Gemstone Company discloses heat treatment as an enhancement used to stabilize and refine the blue hue, and the stone is presented with full provenance from Mozambique as part of our curated parcel of fine beryl material.

Technically the cut and proportions deserve close attention, the stone measures 5.71 millimeters across with a depth of 4.02 millimeters, yielding an approximate depth ratio of 70.4 percent, a value that leans toward a deeper pavilion profile relative to many standard round brilliants. That depth increases apparent color saturation when set, while producing a slightly smaller face up diameter than one would expect from a shallower stone of equal weight. The mixed brilliant approach provides a crown arrangement of kite and triangular facets to optimize scintillation, paired with a pavilion composed of concentric modified facets that reduce windowing and channel light back into the crown. Optical characteristics of beryl include a refractive index in the range of approximately 1.577 to 1.583, and a low dispersion near 0.014, so tactical faceting and high quality polish are required to achieve lively scintillation and a vivid face up appearance despite modest inherent fire. The excellent polish on this example maximizes surface reflection, and the very slightly included clarity grade indicates minute internal features such as thin needles or three phase inclusions that do not detract from transparency or light performance under normal viewing conditions.

The hue and tone of this Mozambique aquamarine are characterized as a delicate sky blue with a subtle greenish undertone prior to treatment, and a pure cool blue face up after calibrated heating. Heat treatment in beryl commonly alters the valence balance of iron impurities, reducing green components and enhancing blue saturation, a standard and widely accepted practice across the trade, and executed here to present a stable, attractive blue. When compared to classic Santa Maria aquamarines from Minas Gerais, Brazil, which are renowned for an intense, saturated azure to cornflower blue with medium to strong tone, this Mozambique specimen reads lighter and more pastel, offering a more ethereal, sea glass appearance rather than the dense oceanic blue associated with Santa Maria material. Compared to aquamarines from the Karakoram region of Pakistan and the adjacent deposits of Afghanistan, which frequently yield medium to strong blue stones with pronounced saturation and occasionally velvety tone, the Mozambique stone is more restrained in intensity and presents higher clarity with fewer color centers, especially after heating. Compared to material from Madagascar and certain African localities, which can trend toward greenish blue and variable tone, this piece retains a cleaner, more pure blue hue post treatment, while still preserving a natural lightness that appeals to buyers who prefer a softer, more luminous blue.

From a practical and connoisseur perspective, this aquamarine is particularly well suited to designs that benefit from subtlety of color and precision of cut, such as bezel set pendants that preserve face up color, solitaire mounts that emphasize the round mixed brilliant geometry, and ring designs where the slightly deeper profile will anchor the stone visually, enhancing perceived saturation under typical lighting. The combination of a mixed brilliant cut and excellent polish compensates for the inherently low dispersion of beryl, producing notable sparkle and even scintillation across the table and facets. The very slightly included clarity grade, evaluated at eye level, assures collectors that the gem is effectively eye clean, and the modest size and standardized dimensions make this stone ideal for precision settings and paired designs. The Natural Gemstone Company stands behind the disclosure of origin and treatment, and we invite technical inquiries about facet proportions, expected table diameter, and mounting recommendations for this Mozambique aquamarine, for buyers who assess gemstones by optical performance, provenance, and the finer points of gem cutting craftsmanship.