4.05 Ct. Ruby from Mozambique

This transparent 4.05 carat oval ruby, measuring 10.45 x 8.46 x 5.04 mm, displays vivid color intensity and a mixed brilliant cut that together create a level of sparkle that is difficult to replicate. At the mineral level this stone is natural corundum, where the compact trigonal lattice and elevated refractive index translate into strong internal reflection. Trace chromium ions impart the rich red hue while subtly enhancing selective absorption, so light that enters the stone is filtered into a saturated red spectrum and then efficiently redirected by the polished facet planes. The mixed brilliant cut used on this oval balances a faceted crown designed for scintillation with a pavilion structure optimized for light return. Facet geometry, precise angles, and excellent polish produce sharp specular reflections and lively scintillation, so movement and changing light reveal repeated flashes rather than a diffuse glow. The oval outline lengthens the light path through the gem, intensifying contrast and producing pronounced flashes along the long axis, while the 4.05 carat weight and depth proportion allow those flashes to register with presence and clarity.

Clarity graded as very slightly included at eye level means the stone remains visually clean, while small internal features can act as secondary reflective surfaces that accentuate pinpoint brilliance without clouding the body color. The ruby has been heat treated, a standard and stable enhancement that improves transparency by modifying rutile and silk inclusions and by stabilizing color saturation, which in turn increases the efficiency with which light is transmitted and returned. Excellent polish and precise facet junctions minimize light leakage, and together with the corundum structure and the skilled mixed brilliant cutting, they produce a sparkle that we regard as unparalleled in comparable material. Origin Mozambique, enhancement heat treated, mixed brilliant cut, very slightly included clarity, vivid color intensity, oval shape, dimensions 10.45 x 8.46 x 5.04 mm, weight 4.05 carats. The Natural Ruby Company provides this gem with full disclosure of its origin and treatment, presented for those seeking a technically refined ruby whose optical performance is defined by structure, cut, and finish.