Parcel of Loose Black or Dark Opal Cabochons

This parcel consists of five oval-shaped loose gemstone cabochons, identified as opals, likely of the black or dark variety based on the body tone. The gemstones exhibit vibrant play-of-color, including neon greens, electric blues, and flashes of orange and red against a dark base. Each stone is cut into a symmetrical oval cabochon with a polished dome. The sizes appear to be relatively uniform, likely ranging between 8mm to 12mm in length, though an exact measurement would require a micrometer. The craftsmanship displays a standard commercial to fine-grade polish, intended for use in jewelry settings such as rings or pendants. One stone is shown from the reverse, revealing a dark, opaque potch or backing, which is characteristic of natural solid black opals or potentially doublet constructions; however, the lack of a visible join line suggests they are solid stones. There are no immediate signs of cracking (crazing) visible through the plastic packaging, though the surface should be inspected for micro-scratches. The vibrant saturation of the green and blue flashes indicates high-quality silica structure. Given the coloration and opal type, these stones are stylistically consistent with Australian material from Lightning Ridge, potentially dating from the late 20th century to the present day.

I have examined the images of this parcel consisting of five oval black opal cabochons. The stones exhibit a dark body tone (N2 to N4) which provides an excellent canvas for the vibrant green and blue play-of-color, with secondary flashes of orange noted in the larger specimens. The saturation is high, suggesting a high-quality silica structure. Based on visual cues, the stones appear to be solid, natural Australian opals, most consistent with material from Lightning Ridge. There is no visible evidence of crazing or significant surface abrasions through the magnification provided. The uniformity in size, approximately 10x8mm, increases the parcel's utility for calibrated jewelry manufacturing. The current market for Australian black opal remains robust due to diminishing yields from traditional mining areas, keeping demand for high-saturation parcels strong. This valuation assumes the stones are solid and have not undergone treatments like smoke or sugar-acid carbonization. Limitations: A definitive appraisal requires an in-person loupe inspection to confirm the absence of 'potch' lines associated with doublets or triplets, which would decrease value by 80%. Professional gemological testing (refractive index and specific gravity) and a formal weigh-in are necessary to confirm exact carat weight and price-per-carat metrics. Provenance documentation from an Australian supplier would further support the valuation.