The fastening for these leaves and flower is loose on the backside, but has not come apart. The shell is slightly lopsided in its setting, but does not wiggle around and seems sturdy. The leaf on the right side extending from the body of the brooch seems to have been soldered back on (check 3rd & 4th photo). The piece seems to resemble a Victorian style, but the clasp is maybe from the 1920s or 30s. When I acid tested the brooch, the 14k acid did not completely disappear, but it faded.
Hence why I believe it is somewhere around 10k - 12k. Check my other listings for more Vintage Jewelry & Collectibles. The item "Antique Victorian Style 10k 12k Gold Carved Shell Cameo Floral Leaf Motif Brooch" is in sale since Monday, March 29, 2021. This item is in the category "Jewelry & Watches\Vintage & Antique Jewelry\Fine\Art Nouveau/Art Deco 1895-1935\Cameos".The seller is "detroit_treasures" and is located in Detroit, Michigan. This item can be shipped worldwide.