ambrotypes
/ˈæmbrəˌtaɪps/
noun
- Early photographs made on glass plates, popular in the mid-1800s, that look positive when held against a dark background.
- She found an old ambrotype of her great-great-grandparents in the attic.
- Unlike modern photos, ambrotypes are unique images that cannot be easily reproduced.
- The museum displayed a collection of ambrotypes from the Civil War era.