0.70 Ct. Topaz from Ceylon (Sri Lanka)

This 0.70 carat emerald cut London blue topaz is a study in disciplined geometry and controlled optical performance, presented by The Natural Gemstone Company. The stone measures 6.04 by 4.07 by 3.05 millimeters, a proportioned rectangular outline that favors a classic emerald cut step faceting scheme. The emerald cut here features broad, parallel crown and pavilion facets arranged in concentric steps, producing a measured interplay of light and dark planes rather than a scattered brilliancy. This faceting style emphasizes color depth and clarity, which suits the intense London blue hue of this specimen. The cutting preserves the table plane and crown angles to optimize face up color saturation while maintaining a flat, broad table that displays the stone with authority when set. The gem is transparent with a clarity grade of very slightly included, evaluated at eye level, and it benefits from an excellent polish that renders facet junctions crisp and reflective.

Color is the defining attribute of this piece, with an intense London blue saturation that reads as a cool, deep ocean blue under incandescent light and as a slightly steelier blue under daylight. The color enhancement method is irradiation, a controlled process we disclose for full transparency, followed by thermal stabilization where required. Irradiation in topaz production is a standard practice that shifts the native color towards the deep blue tones collectors seek, and when properly stabilized, the chroma remains stable under normal wear conditions. The term London blue denotes both a particular tone and saturation range, and this gem’s tone sits in the upper mid range for London blue, offering strong saturation without becoming blackish. The faceting arrangement has been tuned to distribute the color evenly across the table and crown planes, minimizing windowing and color zoning, and ensuring consistent visual impact from most viewing angles.

Clarity and cutting precision contribute directly to the perceived value of this topaz. Very slightly included evaluated at eye level means that inclusions are minimal, typically limited to pinpoint crystals or fine needles that do not interrupt the face up color or the step facet planes. In an emerald cut, inclusions align with facet planes more readily than in brilliant cuts, and the cutter has oriented the stone so that the inclusions, where present, are masked by the step facets and remain unobtrusive. The excellent polish indicates that facet surfaces are smooth and free from polish lines or abrasions, which enhances the stone’s ability to reflect light from broad facet surfaces. Attention to symmetry and facet proportionality is evident in the way internal reflections stack and form parallel banding, a hallmark of well executed step cutting, and the result is a calm, architectural light return that highlights color depth rather than scintillation.

From a craftsmanship and durability standpoint, this topaz is an attractive candidate for enduring jewelry, given its hardness and stable treatment. Topaz rates eight on the Mohs scale, which affords good resistance to everyday scratches, and the emerald cut reduces the visibility of minor abrasion by presenting large, flat facets. The irradiation enhancement applied to achieve the London blue tone is stable under typical usage. Avoiding prolonged exposure to high heat applications and aggressive chemicals preserves the treated color and the integrity of the polish. Routine care consists of gentle cleaning with warm soapy water and a soft brush, and periodic inspection of any mounting to detect potential knocks or prong wear. When set in a bezel or four prong head, the stone’s rectangular proportions and measured pavilion depth will sit securely while showcasing its intense color and calm, step cut reflections.

Provenance and company assurance complete the offering. This London blue topaz originates from Ceylon, Sri Lanka, a source with a long history of producing transparent gem material and skilled lapidary work. The Natural Gemstone Company sources stones in small lots and inspects each gem for color consistency, clarity grading, and cutting quality prior to offering. We provide full disclosure of the irradiation enhancement, and we are prepared to supply supplemental documentation regarding weight, measurements, origin, and our assessment of clarity and polish upon request. For the discerning buyer who values technical merit, this 0.70 carat emerald cut London blue topaz delivers measurable attributes, from precise step faceting and excellent polish to stable, intense color, ensuring that its natural beauty will continue to captivate over the years. Contact The Natural Gemstone Company for bespoke mounting recommendations and certification options.