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Grading Guide
Understanding brightness, play of colour, and different patterns
Colour Play
- Spectro-chromatic: full rainbow spectrum (most valuable)
- Dichromatic: two primary colours
- Monochromatic: single dominant colour
- Pink is the rarest colour
Pattern Types
- Dragon skin: small fractured mosaic pattern
- Stained glass/Cobblestone: medium irregular sections
- Broad flash: large continuous colour areas
- Floral Pattern: Splashes intense colour, typically red on blue
- Ribbon pattern: Rolling waves of colour
- Bryozoan Pattern: tiny network-like imprints of microorganisms on the ammonite shell