Lab-created black onyx. Octagon cut, 8×6mm. Prong set with pave accent stones. An opaque black stone in a geometric eight-sided outline — the stone reads entirely by its silhouette and polished surface rather than by light transmission or internal facet reflections. The pave accent stones fire white brilliance directly against the light-absorbing black face. Minimalist, dark, architectural.

This ring features a lab-created octagon-cut black onyx center stone prong-set in a mounting with pave accent stones around the setting. The octagon cut’s eight-sided outline — a square or rectangle with all four corners cropped at 45 degrees — gives the black onyx a strong geometric silhouette that reads as deliberately architectural on the finger. Because black onyx is fully opaque, the stone’s visual character is defined entirely by its outline shape and its polished surface; the pave accent stones surrounding the setting provide the ring’s light and fire in direct contrast to the onyx’s absolute darkness. Available in 925 sterling silver, yellow gold plated, or rose gold plated, in whole and quarter sizes from US 3 to 10. Handcrafted in Jaipur.

Ring Details

• Stone: Lab-created black onyx — octagon cut, 8×6mm, opaque black
• Setting: Prong set center with pave accent stones
• Metal Options: 925 Sterling Silver · Yellow Gold Plated · Rose Gold Plated
• Sizes Available: US 3 to 10 including quarter sizes

Black Onyx: Opacity, Silhouette, and Surface

Black onyx is a variety of chalcedony — microcrystalline quartz (silicon dioxide, SiO₂) — that is uniformly black, produced through natural formation or through the heat-treating and dyeing of lighter chalcedony material (a practice that has been standard in the commercial black onyx trade since antiquity). Its microcrystalline structure means it has no large internal cleavage planes or facet-reflective surfaces in the conventional gemological sense — light does not enter and refract through black onyx the way it does through transparent or translucent stones. Instead, black onyx absorbs virtually all incident light across the visible spectrum: its black color is the result of near-total absorption, with only a thin specular surface reflection from the polished outer face producing the stone’s characteristic glossy sheen. The result is a stone whose entire visual identity is carried by two elements: its outline silhouette (the shape of the cut as seen from above) and its surface polish (the quality of the glossy reflective layer on the stone’s face). Everything the eye perceives when looking at a black onyx ring is the cut’s shape and the surface’s gloss — no internal color, no fire, no transparency, no depth illusion. This makes the choice of cut format critically important for black onyx in a way it is not for transparent stones: the cut is the entire visual statement. Hardness is approximately 6.5–7 Mohs.

The Octagon Cut on an Opaque Stone

The octagon cut — a rectangular or square outline with all four corners cropped at 45 degrees, producing an eight-sided silhouette — is the same outline geometry as the Asscher cut and the emerald cut with cropped corners. On a transparent faceted stone, the octagon cut produces step-cut internal facets and the hall-of-mirrors depth effect. On an opaque stone like black onyx, the facet arrangement beneath the table surface is irrelevant to the visual result — what matters is only the top-down silhouette. The octagon outline on black onyx produces a strong graphic shape: eight sides meeting at precise angles, the cropped corners preventing the sharp-corner fragility of a true rectangle while maintaining the rectangular format’s architectural character. The 8×6mm size presents the stone as a clearly defined, substantial shape on the finger — wide enough to read as a statement stone, elongated enough that the rectangular proportion is visible and intentional. In the minimalist and dark aesthetic, the octagon black onyx reads as a deliberate geometric shape choice — a graphic element worn on the finger — rather than a light-performance stone.

Pave Accents Against Black: Maximum Light Contrast

The pave accent stones surrounding the center onyx setting are faceted white stones (moissanite or CZ) set in a pave arrangement — small round brilliant stones set closely together with minimal metal visible between them, creating a surface of continuous sparkle. Against a black onyx center, the white pave stones create the maximum possible contrast in both color (white vs. black) and optical character (transparent, light-active, fire-producing vs. opaque, light-absorbing, surface-only). The pave stones’ round brilliant facets generate white light return (brilliance) and spectral fire; the black onyx center stone absorbs both. The eye reads the pave’s active, kinetic sparkle as more vivid and intense against the onyx’s absolute stillness than it would against any other background material. The black center makes the white pave appear brighter; the white pave makes the black center appear deeper — each material pushes the other toward its visual extreme through simultaneous contrast.

Dark Aesthetic and Styling

Black onyx in a geometric cut occupies a specific position in contemporary jewelry aesthetics — it is the intersection of minimalism (the stone’s total absence of color or internal light play demands nothing from the viewer beyond recognition of its shape) and drama (the stone’s absolute black and the pave’s white fire create a high-contrast composition that reads as bold regardless of scale). This ring stacks well with plain bands, with other dark stone rings, or with white stone rings where the black onyx provides the visual anchor. It works as a statement piece worn alone on a single finger or as part of a deliberate dark-aesthetic stack.

Care Instructions

• Remove before swimming, showering, or applying lotions and perfumes (especially for plated finishes)
• Black onyx is ~6.5–7 Mohs — suitable for ring wear with reasonable care; avoid contact with harder stones or abrasive surfaces that could scratch the polished face
• The polished surface of the onyx is its entire visual character — surface scratches are more visible on opaque black stones than on transparent faceted stones; handle with care
• Clean gently with a soft, slightly damp cloth; avoid soaking or harsh chemical cleaners
• Store in a padded box when not worn

Sizing & Packaging

Please refer to our size guide image before ordering. Your ring ships in secure protective packaging. Any display props shown in photos are for styling purposes only.

Questions about sizing, metals, or the stone? Message us — we’re happy to help.