This is a salt print from a wet plate collodion negative.
It’s toned with gold toner.
Waxed with beeswax, for better archival quality.
Format 25×30 cm or 10×12″. Mat size is 40x50cm or 16×20″.
The albumen print is mounted in two acid free mat sheets and mounted with plastic corners.
This negative was made in 2015 and the print was made in 2020. you can see the making of video on THIS LINK.
The price is 350 EUR, free shipping.