50 actual shades of gray
A 1912 book by Robert Ridgway named 1,115 colors, including dozens of shades of gray
Robert Ridgway was a famous ornithologist who wrote an eight-volume work on The Birds of North and Middle America. (Three more volumes were completed by a colleague after his death.) He saw a need for standardized color naming in ornithology and other sciences that had to classify large quantities of natural specimens, and published a system for identifying and naming 1,115 colors in 1912.
Ridgway's Color Standards and Color Nomenclature was not the first attempt to standardize colors. Taxonomies of 100 to 400 color names had been published through the 19th century and more rigorous systems based on spectrum analysis or color-wheel placement had used symbols or numbers to represent exact combinations of color features (hue, tone, light, shade, etc.). Ridgway's, however, was the first to provide such a finely divided color categorization that also used words from natural language, which, he argued, despite their imprecision, were more useful to naturalists.
The book was printed with 1,115 painstakingly produced color plates, including more than 100 shades of gray. The names for those grays include mellifluous terms like plumbeous (the color of lead), plumbago (a flower with lead-colored petals), glaucous (from the Latin/Greek for bluish-gray), vinaceous (wine-colored), cinerous (cinder-colored), and heliotrope (a flower with purplish petals). Varley is named for landscape painter John Varley and Payne after painter William Payne. After you read this list, you can proudly tell all your friends you were intellectually stimulated by reading 50 shades of gray.
1. Cadet Gray2. Carbon Gray3. Castor Gray4. Cinereous5. Clear Blue-Green Gray6. Court Gray7. Dawn Gray8. Drab-Gray9. French Gray10. Glaucous-Gray11. Dark Glaucous-Gray12. Deep Glaucous-Gray13. Gull Gray14. Light Gull Gray15. Hathi Gray16. Heliotrope-Gray17. Dark Heliotrope Slate18. Iron Gray19. Lavender-Gray20. Lilac-Gray21. Mineral Gray22. Mouse Gray23. Blackish Mouse Gray24. Neutral Gray25. Dusky Neutral Gray26. Olive-Gray27. Payne's Gray28. Light Payne's Gray29. Pale Payne's Gray30. Pearl Gray31. Plumbeous32. Blackish Plumbeous33. Plumbeous-Black34. Dark Plumbeous35. Plumbago Gray36. Dark Plumbago Gray37. Puritan Gray38. Purplish Gray39. Pallid Purplish Gray40. Sky Gray41. Slate Color42. Slate-Gray43. Slate-Black44. Blackish Slate45. Smoke Gray46. Storm Gray47. Varley's Gray48. Vinaceous-Gray49. Deep Vinaceous-Gray50. Violet-Gray