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Natural, Cultured & Imitation Pearls — Terminology & Classification

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Natural, Cultured & Imitation Pearls — Terminology & Classification © CIBJO 2007. All rights reserved. 2007-6 2007-11-06 CIBJO/GEM MATERIALS CIBJO/SECTOR 3/PEARL COMMISSION THE PEARL BOOK Natural, Cultured & Imitation Pearls — Terminology & Classification (Including information on modifications) draft with edits CIBJO standard E © CIBJO 2007. All rights reserved. PEARL COMMISSION 2007-6 Foreword .......................................................................................................................................................................... xii Introduction .................................................................................................................................................................... xiv 1. Scope .......................................................................................................................................................................... 1 2. Normative references ................................................................................................................................................ 1 3. Pearl Categories ........................................................................................................................................................ 1 4. Normative Clauses .................................................................................................................................................... 1 4.1. General .................................................................................................................................................................... 1 4.2. The use of terms .................................................................................................................................................... 2 4.3. Modifications and/or treatments .......................................................................................................................... 4 4.4. Nacre thickness ..................................................................................................................................................... 5 4.5. Imitations or simulants.......................................................................................................................................... 5 4.6. Weight and measurement ..................................................................................................................................... 6 4.6.2. Measurement ...................................................................................................................................................... 6 5. Terms and definitions ............................................................................................................................................... 7 5.1. Abalone ................................................................................................................................................................... 7 5.2. Abalone Cultured Blister ....................................................................................................................................... 7 5.3. Abalone Pearl ......................................................................................................................................................... 7 5.4. Actinonaias pectorosa .......................................................................................................................................... 7 5.5. Adductor muscle .................................................................................................................................................... 7 5.6. Akoya ...................................................................................................................................................................... 7 5.7. Akoya cultured pearl ............................................................................................................................................. 7 ii © CIBJO 2007. All rights reserved. PEARL COMMISSION 2007-6 5.8. Akoya pearl oyster ................................................................................................................................................. 8 5.11. Assembled .......................................................................................................................................................... 8 5.12. Assembled Cultured Blister .............................................................................................................................. 8 5.13. Atlantic Pearl Oyster .......................................................................................................................................... 8 5.14. Australpearls ...................................................................................................................................................... 8 5.15. Baroque ............................................................................................................................................................... 8 5.16. Bead ..................................................................................................................................................................... 8 5.17. Beaded Cultured Pearl ....................................................................................................................................... 8 5.18. Bivalve ................................................................................................................................................................. 9 5.19. Biwa Cultured Pearl ........................................................................................................................................... 9 5.20. Black Cultured Pearl .......................................................................................................................................... 9 5.21. Black-lipped Pearl Oyster .................................................................................................................................. 9 5.23. Bleaching ............................................................................................................................................................ 9 5.24. Blister cultured pearl ......................................................................................................................................... 9 5.25. Blister pearl ......................................................................................................................................................... 9 5.26. Blisters ................................................................................................................................................................ 9 5.27. Bombay pearls .................................................................................................................................................. 10 5.30. Button-shaped pearl ........................................................................................................................................ 10 5.31. Carat .................................................................................................................................................................. 10 5.32. Cassis madagascarensis ................................................................................................................................ 10 5.33. Cerclé ................................................................................................................................................................ 10 5.34. Ceylon Pearl Oyster ......................................................................................................................................... 10 5.35. Chambered nautilus ......................................................................................................................................... 10 5.36. Chinese drilling ................................................................................................................................................ 10 iii © CIBJO 2007. All rights reserved. PEARL COMMISSION 2007-6 5.37. Choker ............................................................................................................................................................... 11 5.38. Circled cultured pearl ...................................................................................................................................... 11 5.39. Clam pearl ......................................................................................................................................................... 11 5.40. Cleaning ............................................................................................................................................................ 11 5.41. Coating .............................................................................................................................................................. 11 5.42. Collar ................................................................................................................................................................. 11 5.43. Commercial Name ............................................................................................................................................ 11 5.44. Composite cultured pearl ................................................................................................................................ 11 5.45. Conch ...............................................................................................................................................................
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