- 21:59, 5 January 2006 diff hist -23,358 AY Honor Shells - Advanced Answer Key
- 21:58, 5 January 2006 diff hist -23,369 AY Honor Shells - Advanced Answer Key added more about physical properties of nacre to end of first paragraph; added paragraph about iridescence
- 21:48, 5 January 2006 diff hist -23,880 AY Honor Shells - Advanced Answer Key "clay platelets" in picture caption changed to "aragonite platelets"
