1.56 Ct. Cobalt Spinel from Tanzania

This listing features a single transparent blue cobalt spinel weighing 1.56 carat, presented in an emerald cut with precise proportions, and originating from Tanzania. The stone measures 7.73 x 6.24 x 3.58 mm, offering a compact but substantial presence for a colored gemstone of this species. Clarity is graded as very slightly included at eye level, indicating minimal inclusions that do not detract from overall transparency. Color intensity is described as dark, contributing to a deep, saturated blue hue that is characteristic of cobalt rich spinel. The polish has been evaluated as excellent, and there has been no enhancement, reflecting a natural and untreated material. The Natural Gemstone Company provides this specimen with clear documentation of its physical characteristics and origin, supporting informed appraisal and design decisions.

The weight of 1.56 carat is central to the gems value and rarity profile, and it is important to consider how carat weight functions in the colored gem market. Unlike common gem species where extreme sizes are readily available, cobalt spinel typically occurs in smaller, gem quality crystals, making stones above one carat noticeably rarer. As weight increases, market scarcity increases at a nonlinear rate, and the premium per carat often rises accordingly. A 1.56 carat cobalt spinel occupies a meaningful segment of the market where availability tightens, particularly for specimens that also meet standards of good transparency, strong color saturation, and fine finish. For collectors and designers who prioritize natural, untreated material from a reputable source, this weight enhances desirability and contributes positively to long term value retention.

The emerald cut in this example is chosen to emphasize color and clarity while maintaining elegant geometric lines, and the cut interacts with the 1.56 carat weight to maximize visual impact. The rectangular facets and step cutting create broad planes that showcase the depth of tone and allow the dark blue color to present uniformly across the table. The dimensions of 7.73 x 6.24 x 3.58 mm translate into a stable footprint for rings, pendants, and bespoke settings, and the stone sits with a proportional profile that balances surface area and pavilion depth. Very slightly included clarity at eye level means that minor inclusions are present but do not interrupt the overall visual appeal, and the excellent polish ensures smooth facet junctions and consistent light return. Because there has been no enhancement, the observed color and clarity are intrinsic characteristics of the material, and the combination of weight, cut, and finish allows the gem to read as a purposeful, substantial element in a variety of jewelry applications.

From a practical perspective, the 1.56 carat weight positions this cobalt spinel as an excellent choice for a center stone in medium scale settings, or as a refined accent in pieces where a natural deep blue anchor is desired. The natural origin in Tanzania is relevant for provenance considerations, and the absence of treatment simplifies valuation and long term care expectations. The Natural Gemstone Company emphasizes factual disclosure of attributes, and we note that detailed imagery and handling notes are available on request, supporting design planning and appraisal. Care recommendations follow standard practice for spinel, with avoidance of harsh chemicals and ultrasonic cleaners when inclusions or settings could be vulnerable, and routine inspection of mounting integrity is advisable. In summary, the 1.56 carat weight is a defining attribute of this cobalt spinel, amplifying its rarity relative to smaller material, enhancing its presence in wearable designs, and contributing materially to its market value, while the combination of natural origin, very slightly included clarity, dark color intensity, emerald cut, and excellent polish makes this offering a considered choice for collectors and jewelers seeking an untreated, well finished colored gemstone.