Description
Explore this Natural Dark Opal Type 1, an understated gemstone from Lightning Ridge, with these unique characteristics:
- Variety: Natural Dark Opal Type 1
- Body Tone: Black N6 (13)
- Brightness: Very Dull
- Transparency: Translucent
- Colour: Green-Blue with faint tones
- Shape: Oval Outline
- Profile: Low Cabochon
- Pattern: Blocky Pattern
- Display: Weak or blank from three angles
- Colour Distribution: 20–29% coverage
- Inclusions: None
Physical Properties:
- Absorption Spectra: 660nm, 470nm
- Birefringence: None
- Category: Mineraloid (Amorphous)
- Cleavage: None
- Crystal Form: Amorphous, pseudomorph, botryoidal
- Crystal Habit: Irregular ‘nodular’ veins
- Composition: Hydrous silicon dioxide (3–21% water content)
- Density: 2.09
- Transparency: Transparent to opaque
- Fluorescence: May phosphoresce under long/short wave UV
- Fracture: Conchoidal – Uneven
- Group: Silicates; Tectosilicates; Silica Group
- Lustre: Vitreous to Resinous
- MOHS Scale: 4.5 – 6.5
- Polish: 2.15 ± 0.08-0.09
- Refractive Index (R.I.): 1.450 ± 0.020
- Specific Gravity: 1.98 – 2.25
- Streak: White
- Solubility: Methanol, Humic, Hydrofluoric Acid
Valuation:
- Carat Weight: 5.48 Carats
- Price Per Carat: $16.98
- Total Value: $93.05
This opal’s subtle green-blue hues and blocky pattern offer a delicate beauty, ideal for collectors seeking a more understated gemstone. Its affordability makes it a perfect entry-level choice for those exploring opals from the renowned Lightning Ridge.
Note: This valuation was conducted for insurance purposes and is intended for private and confidential use only.
