Freeform cabochon of Australian opal from Lightning Ridge, measuring 8.62 × 4.70 × 1.93 mm and weighing 0.50 carats. The neutral grayish body (N8 classification on the GIA scale) acts as a canvas for a subtle play of color in turquoise green and aqua blue: the flashes are faint, diffuse, and continuous, lacking the intensity of a black opal but possessing a discreet elegance that varies gently with movement. Unique piece numbered nr.18.
Piece Data
| Mineral |
Australian Opal from Lightning Ridge |
| Scientific name |
SiO₂·nH₂O (amorphous hydrated silica) |
| Hardness |
5.5–6 Mohs |
| Crystal system |
Amorphous |
| Origin |
Lightning Ridge, New South Wales, Australia |
| Dimensions |
8.62 × 4.70 × 1.93 mm (freeform) |
| Weight |
0.50 carats |
| Body color |
N8 (neutral grayish) |
| Play of color |
Subtle turquoise green with aqua blue hues |
| Play of color intensity |
Subtle / low, diffuse light effect |
| Finish |
Polished on upper face |
| Treatment |
Untreated |
| Unique piece |
Yes — numbered piece nr.18, one of a kind |
Piece Characteristics
This piece represents the most delicate and tranquil facet of Australian opal. The N8 body (grayish, close to white on the GIA scale where N1 is black and N9 is white) produces a diffuse light effect, without the intense flashes of black opal. The turquoise-green play of color flows like a gentle current within the stone, more contemplative than spectacular.
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Elongated freeform: the elongated organic outline is ideal for earrings, small pendants, or as a secondary element in compositions.
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Thinness of 1.93 mm: the thinness of the piece gives it lightness and an elegant profile. It is a low-profile piece, primarily visible from the top face.
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0.50 carats: very light weight, ideal for earrings or pendants that should not add noticeable weight.
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N8 Color: light or neutral body colors (N7–N9) are more common than black (N1–N4). The rarity of Lightning Ridge is not in the body color but in the provenance and the delicacy of this particular play of color.
Jewelry Applications
The small scale (8.62 × 4.70 mm) and delicate appearance of this piece make it suitable for minimalist jewelry and pieces of discreet elegance:
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Solitaire earring: a single earring in 925 silver with a very fine bezel setting (0.5–0.7 mm) that leaves most of the opal's surface visible.
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Minimalist pendant: on a fine 40–45 cm chain, close to the neck, where the subtle sparkle is visible up close.
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Second element in earrings: combined with a more intense opal piece like nr.16 (triangular, 15.1 ct), it can act as a calmer counterpoint in an asymmetrical earring design.
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Delicate wire wrapping: the small dimensions allow for a minimal wrap of 2-3 coils in 0.6–0.8 mm thick 925 silver so as not to visually overpower the stone.
The subtle turquoise green works especially well with polished mirror silver (which amplifies luminosity) and with white gold (a similar color temperature combination).
Australian Opal Care Guide
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Cleaning: use a slightly damp, soft microfiber cloth. Never submerge in liquids.
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Avoid ultrasonics: vibrations can cause internal microfractures.
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Avoid steam and temperature changes: opal contains structural water (3–21% depending on the piece) that can be affected by temperature and humidity variations.
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Avoid impacts: the thinness of 1.93 mm makes this piece particularly sensitive to impacts. Always store in an individual padded case.
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Avoid prolonged intense UV light exposure: it can alter the opal's water content in the long term.
History and Provenance
Lightning Ridge is the only place in the world where gem-quality black opals are mined. However, not all opals from Lightning Ridge are black: the same deposit also produces opals with gray (N7–N8), white (N9), and crystalline bodies, depending on the specific sedimentary layers where they formed. This nr.18 comes from a vein with grayish body formation, which makes it distinct from the more sought-after blacks but equally authentic and of verified provenance.
Frequently Asked Questions
Why is the play of color in this piece subtle and not intense like other opals?
The play of color in opal depends on the size and regularity of the silica spheres that diffract light. The N8 body (grayish) and the low intensity of the play of color indicate that the nanospheres in this piece preferentially diffract wavelengths from the green-blue spectrum with moderate intensity. This is not a defect but a characteristic: each opal has its own optical "temperament."
Are the dimensions of 8.62 × 4.70 mm sufficient for silver setting?
Yes. The dimensions, although small, are perfectly viable for setting in 925 silver. A closed bezel 0.5 mm high and 0.5 mm thick is sufficient to securely hold the piece. The low profile (1.93 mm thick) facilitates setting as it does not require a deep cradle.
Does opal from Lightning Ridge guarantee higher quality than from other provenances?
Lightning Ridge is recognized by international gemological laboratories as the most valued provenance for black opal. However, this piece has an N8 body (grayish), not black. The Lightning Ridge provenance confirms the authenticity of the mineral and its origin, but the value of each piece also depends on the play of color, dimensions, and specific characteristics of each specimen.
Note: The meanings of crystals are spiritual supports and do not replace medical prescriptions.
