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1.39 Ct. Topaz from Ceylon (Sri Lanka)
This loose stone ships by Jan 4
Item ID: | K20519 |
|---|---|
Dimensions (MM): help | Length: 8.11 Width: 5.81 Height: 4.09 |
Weight: | 1.39 Ct. |
Color: help | Swiss Blue |
Color intensity: help | Intense |
Clarity: help | Very Very Slightly Included |
Shape: help | Oval |
Cut: | Mixed Brilliant |
Cutting style: | Faceted |
Enhancements: help | Irradiation |
Origin: help | Ceylon (Sri Lanka) |
Per carat price: help | $40 |
This oval Swiss blue topaz offered by The Natural Gemstone Company is a transparent, well proportioned stone weighing 1.39 carats, with dimensions of 8.11 by 5.81 by 4.09 millimeters. The length to width ratio is approximately one point four, which provides an elegant elongation without stretching the pavilion, and the depth proportion is close to fifty nine percent relative to the average diameter, a balance that preserves weight while allowing optimal light performance. The cutting style is a mixed brilliant, designed to combine the scintillation attributes of a brilliant crown with a pavilion geometry that maximizes return for topaz specific optics. Clarity is recorded as very very slightly included at eye level, indicating that the gem is effectively eye clean, with only minute features that do not disrupt face up appearance or light passage. Color intensity is categorized as intense Swiss blue, the tone and saturation yielding a vivid, evenly distributed blue across the table and crown facets, and the finish is described as excellent polish, with crisp facet junctions and mirror like facet surfaces.
From a faceting and craftsmanship perspective, this gem exhibits the hallmark precision of a refined mixed brilliant cut. The crown is arranged with modified brilliant facets that produce lively scintillation when the stone is tilted, while the pavilion facet set is calculated to the refractive index range of topaz to encourage internal reflection rather than leakage. Topaz refractive indices lie between one point six zero nine and one point six four three, and facet angles for this piece were optimized within that window to enhance return without creating optical extinction zones. The cutter preserved a thin to medium girdle to allow secure setting without excessive weight loss, and the table and crown heights are proportioned to create balanced light dispersion and contrast. The excellent polish increases apparent brilliance by reducing surface scattering, and precise symmetry ensures that facet reflections align to create coherent light patterning at the table, producing a crisp, lively face up presentation.
In comparative terms, the brilliance and visual appeal of this Swiss blue topaz differ in predictable and attractive ways from more commonly encountered blue gemstones. Compared with aquamarine, which is a beryl species with refractive indices near one point five seven to one point five eight three, the topaz has a higher refractive index, and therefore it registers greater return of light and a brighter appearance under the same lighting. Aquamarine tends to display a softer, more watery glow, whereas this topaz displays punchier brilliance and a more defined scintillation pattern, owing to both material optics and targeted facet cutting. Compared with blue sapphire, which has a higher refractive index and greater toughness, the sapphire often presents deeper saturation and stronger fire, however this Swiss blue topaz stands out for its vivid lighter blue and for the way the mixed brilliant cut exploits topaz optical properties to create crisp sparkle across the table. Against blue zircon, which can show exceptional fire due to higher dispersion, this topaz offers steadier, more uniform blue color without excessive dispersion, and it is less prone to the brilliance variability that some highly dispersive stones show when facets are misaligned. Against diamond, topaz has much lower refractive index and dispersion, therefore it will not exhibit the same level of fire, yet when cut and polished to exacting standards its scintillation and color are exceptionally attractive in jewelry contexts where a vivid blue focal point is desired.
Technical considerations for use and care are important for buyers who appreciate craftsmanship. The presented topaz originates from Ceylon Sri Lanka, a locality known for gem quality material and expert cutting traditions. The stone has been enhanced by irradiation to produce the Swiss blue coloration, a common and stable treatment for blue topaz when followed by controlled thermal processing, and the resulting color is considered stable under ordinary wearing conditions. Topaz rates eight on the Mohs hardness scale, offering good durability for rings and pendants, but it has distinct basal cleavage, therefore care should be taken to avoid sharp blows and extreme thermal shock. Ultrasonic cleaning is possible in many cases, however for stones with any internal stress or surface nicks we recommend professional advice prior to ultrasonic use. For setting, an open gallery with prong mounts will allow maximum light entry and emphasize scintillation, whereas deep bezel settings will mute the lively face up presentation. If requested, The Natural Gemstone Company can provide high resolution imaging, optional independent laboratory documentation, and recommendations for complementary mounting designs to showcase this 1.39 carat oval Swiss blue topaz, ensuring the cutting qualities, color intensity, and excellent polish are preserved and presented to their fullest advantage.




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