Materials
- Alabaster (mineral) (stone)2 objects
- Albumen paper184 objects
- Albumen silver print1 objects
- Alder (wood)1 objects
- Alder root93 objects
- Alizarin (natural colorant)8 objects
- Alpaca (wool)10 objects
- Aluminum (metal)84 objects
- Amazonite1 objects
- Amber2 objects
- Amber (fossil resin)26 objects
- Amethyst114 objects
- Amphibolite4 objects
- Andesite17 objects
- Andesite (pinkish)1 objects
- Andradite5 objects
- Angora wool1 objects
- Anhydrite (blue anhydrite?)1 objects
- Anhydrite (blue)1 objects
- Aniline3 objects