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3.13 Ct. Spinel from Burma (Myanmar)
Item ID: | K18620 |
|---|---|
Dimensions (MM): help | Length: 9.2 Width: 7.7 Height: 5.83 |
Weight: | 3.13 Ct. |
Color: help | Purple |
Color intensity: help | Medium Intense |
Clarity: help | Eye Clean |
Shape: help | Cushion |
Cut: | Mixed Brilliant |
Cutting style: | Faceted |
Enhancements: help | Heat Treated |
Origin: help | Burma (Myanmar) |
Per carat price: help | $400 |
This transparent purple spinel offered by The Natural Gemstone Company weighs 3.13 carats and is fashioned in a cushion shape measuring 9.20 by 7.70 by 5.83 millimeters, yielding an overall depth of approximately 69 percent. The gem is cut in a mixed brilliant style, combining a brilliant-faceted crown with a pavilion designed to balance light return and scintillation. It is graded eye clean at standard viewing distance, has a medium intense color saturation, and shows an excellent polish. The stone is heat treated to enhance and stabilize its purple tone, and its documented geographic origin is Burma, Myanmar, a region historically esteemed for producing spinels of notable color and clarity. These specific dimensions and the mixed brilliant execution deliver a substantial face-up presence while preserving optical depth, making the piece suitable for a range of jewellery settings where both color and brilliance are priorities.
The spinel’s intrinsic crystal structure and optical constants are central to the exceptional sparkle observed in this stone. Spinel crystallizes in the isometric system, producing isotropic optical behavior, which means light passes through the crystal without double refraction, preserving the purity and directionality of reflected light from each facet. With a refractive index in the vicinity of 1.72, spinel provides strong internal reflection, so properly angled facets return a high proportion of incident light to the viewer, resulting in crisp, lively brilliance. Although spinel’s dispersion, commonly cited near 0.018, is lower than that of diamond, the combination of high refractive index, precise mixed brilliant faceting, and excellent polish produces pronounced scintillation and well-defined flashes of color rather than the rainbow fire typical of higher dispersion gems. The cushion outline and mixed brilliant arrangement emphasize broad, contrasting light and dark facets across the table and pavilion, creating a pattern of lively flash and contrast that appears more coherent and consistently bright than many other colored stones. Because the gem is eye clean, there are minimal internal interruptions to light paths, allowing mirror-like reflections from facet junctions to reach the observer without scattering. The heat treatment applied is a stable enhancement that optimizes the stone’s medium intense purple, reducing brownish modifiers and increasing the clarity of color, which in turn enhances the perceived brilliance because color saturation and light return work together to define the gem’s visual impact.
Practical attributes further support the spinel’s distinctive brilliance and suitability for everyday wear. Spinel’s hardness of approximately 8 on the Mohs scale gives it durable resistance to scratching, a useful property for rings and frequently worn pieces, while a specific gravity near 3.6 contributes to a substantial, weighty feel relative to its dimensions. The combination of robust hardness, excellent polish, and carefully maintained proportions ensures that the polished facet faces remain sharp and reflective over time, preserving the gemstone’s lively performance. When considered for setting, the cushion shape and 3.13 carat weight present versatile design options, from classic solitaires to halo or three-stone settings where the uniformity of face-up color and sustained brilliance are desirable. For those concerned with treatment and provenance, the stone’s heat treatment is a stable enhancement commonly accepted in the trade, and Burma provenance is documented and recorded, adding contextual value. The Natural Gemstone Company provides accurate measurements and professional grading observations to assist in design and purchasing decisions, and can advise on mounting choices that will maximize light return and protect the pavilion and girdle. In sum, this Burmese purple spinel combines the inherent optical advantages of spinel’s crystal chemistry with expert cutting and finishing to produce a sparkle and presence that distinguish it among commonly used colored gemstones.




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