Jade's Tintypes & other Antique Photographs
What is an Ambrotype? The process was first introduced in 1854 and lasted until roughly the Civil War. A negative was produced on a piece of glass, and then hand-colored or decorated if that was desired. Then some sort of black backing (felt, paper, or black paint) was applied to the back of the glass. This would make the image appear positive. A brass preserver was next applied, and the image placed in a case. A reason that the ambrotype fell out of popularity so quickly was because during the Civil War, soldiers and loved ones wanted to mail photos, but most often ambrotypes would break. A new process, the tintype, had been invented in 1856, and that gained popularity as a portable image which was much more durable.
Ruby Ambrotypes are somewhat different from the normal process, in that they used colored glass (usually red, sometimes green) and the negative was placed on that. Because the glass was colored the image appeared more solid than it would on normal glass. You can tell if you have one of these by holding it up to a light. The glass will clearly be colored. These are more valuable than normal ambrotypes.