Description
Dark opal is lighter than black opal and darker than white opal.
Variety: Natural Dark Opal Type 1
Body Tone: Dark N6 (13)
Brightness: Average
Transparency: Translucent
Colour: Orange-Green
Hue: Normal Tones
Outline: Triangle
Profle: Medium Cabochon
Origin: Lighting Ridge
Pattern: Mixed Pattern
Display: Weak or Blank 1 Angle
Distribution: 50 – 59%
Inclusions: 5% of Face
MOHS Scale: 4.5-6.5
Polish: 2.15+0.08-0.09
R.F.I.: 1.450+0.020
Spec Gravity: 1.98 – 2.25
Carat Weight: .80 Carats
Formula: Si02nH20
Fracture: Conchoidal – Uneven
Lustre: Vitreous – Resinous
Flourescence: May phosphoresce in long /short wave
Absorption: Spectra 660nm, 470nm
Category: Mineraloid (Amorphorous)
Crystal Habit: Irregular ‘nodular’ Veins
Composition: Hydroussilicondioxide.3-21%/weight
Crystal Form: Amorphous, pseudomorph, botryoidal
