Lightning Ridge Black Opal

Introduction

Lightning Ridge in New South Wales produces the world's most valuable
opal variety: black opal. The dark body colour provides exceptional
contrast for play-of-colour, creating the most dramatic and sought-after
opal specimens in the world.

Source

Lightning Ridge characteristics:

Location: Northern New South Wales, near Queensland border
Discovery: Opal found 1901; major production from 1903
Geology: Cretaceous sedimentary opal deposits
Mining: Underground shaft mining; individual claims
Character: Opal-bearing layer at various depths
Status: Heritage mining area; ongoing production

Body Tone

Characteristics

What defines Lightning Ridge black opal:

Body Colour

Range: Black to dark grey (N1-N4 on body tone scale)
Ideal: N1 (jet black) with bright play-of-colour
Dark grey: N2-N4 still considered "black opal"
Contrast: Dark background maximizes colour display

Play-of-Colour

Spectrum: All spectral colours possible
Brightness: Key value factor
Distribution: Even coverage most valuable
Red: Rarest and most valued colour
Directionality: Face-up display critical

Famous Patterns

Recognised pattern types:

Harlequin

Mosaic of distinct colour patches
Angular, checkerboard-like pattern
Rarest and most valuable pattern
True harlequin extremely scarce

Broadflash

Large sweeping colour zones
Colours roll across stone surface
Dramatic visual effect
Highly prized pattern

Pinfire

Small points of colour
Sparkle effect across surface
Common pattern type
Value depends on brightness and coverage

Rolling Flash

Colour moves with stone rotation
Dynamic, changing display
Attractive and valued
Shows opal's unique optical nature

Pattern Value Scale

Pattern	Relative Value	Notes
Harlequin	Highest	True harlequin extremely rare
Broadflash	Very High	Large colour zones; dramatic
Flagstone	High	Rectangular colour patches
Rolling flash	High	Dynamic colour movement
Floral	Medium-High	Flower-like colour patterns
Pinfire	Medium	Depends on brightness
Flash	Medium	Directional colour display

Quality Assessment

Evaluating black opal quality:

Body tone: Darker (N1-N2) more valuable
Brightness: Vivid > bright > subdued > dull
Pattern: Harlequin > broadflash > pinfire
Colour range: Full spectrum > limited colours
Red fire: Presence of red adds significant value
Play distribution: Even coverage preferred
Shape: Well-formed ovals/cushions command premium
Thickness: Adequate depth for durability

Market Position

Black opal in the gem market:

Value: Most expensive opal variety
Price range: $100 to $20,000+ per carat
Exceptional stones: Six-figure prices possible
Supply: Increasingly scarce for fine quality
Investment: Strong collector interest
Certification: Origin certification adds value