This is a very nice piece; I have copied information about the process and era of this type of photographic work. Please note my posted photos to see further detail. Opalotypes were printed on sheets of opaque, translucent white glass; early opalotypes were sometimes hand-tinted with colors to enhance their effect. You can learn more about this process on line. The item "2 Antique Opalotype Milk Glass Photo Young Man Civil War Era Velvet Case c1867" is in sale since Monday, October 5, 2020.
This item is in the category "Collectibles\Photographic Images\Vintage & Antique (Pre-1940)\Other Antique Photographs". The seller is "dmc1119" and is located in Delmar, Maryland. This item can be shipped to United States.