I have wanted a cameo bracelet ever since I passed on one at an auction just after we got back to NY. Despite Mom offering to buy it for me, I couldn’t justify the purchase while we were both unemployed and homeless.
When I see cameos, I think of my Grandma Worden. Cameos and pearls and daisies and yellow roses and heart ornaments and doves. Cameos because I have a few of hers.
Here is a cameo bracelet dated to the 1850s at the Old Sacramento Living History Progam. Its cameos are lava. They are set in simple wrapped settings and joined with simple rings. The focus is on the cameos. The clasp is a box or tab clasp that inserts into the last cameo.
The seller of this lava cameo bracelet with chalky coloring attributes the piece as Italian and dates it to call 1865. It has a similar wrapped setting and clasp. This set of photos shows the back of the bracelet and settings nicely.
I found a bracelet of cameos while yardsale hopping. It was priced so low, I gave them more. (It was a fundraising sale.) It is petite and actually fits my wrist while most bracelets don’t. It is made of nine shell cameos set in simple settings similar to those above, with a box clasp. 
Each of the cameos is different. Left to right: The first has a smaller face, detailed hair, a flower high on her head, and a low draped neckline with flower. Her nose is straight and moderate.
The second looks left. Her head is larger, running off the oval. The shell less pink. Her nose is smaller, more button like. The flower in her hair is further back. Her neckline is higher with a rough flower on the edge. This is one of the thinner ones.
The third has orange in her hair. She has a different face, which looks right.She has the cute little button nose. She has a flower both at her high neckline and back of her hair.
The fourth is another smaller face. Her hair flower and shoulder flower are both huge. She has a thin, straight nose.
The fifth is the thicker cameo. Her flower, set on top of her coiffure rises above the setting. She has the largest nose of the set. Her neckline swoops.
The sixth is pale and subtle. She barely photographs. In person, her carving is very delicate.
Seventh has her head slightly turned down. Her shell is not as pink, not as white as the others. The strands of her hair are quite amazing, the strands being well defined. She has a hair flower set to the back and shoulder flower.
The other left facing is the eighth. This is also a thicker cameo, with a higher raised flower. The placements put the two palest nearly at center, with the two thickest bookending them. Her nose is whee as there is little depth to her profile, but there is detail. In a way, she seem the eldest of the strand of ladies.
The longest neck can be found on the ninety. She has a little orange in her hair along with her flowers set high to the back. Her nose is short and straight.
Ten has more petals in each of her flowers. She almost has a rougher face. Either that or she is smiling. Her nose is straight.
The final lady has only a hair flower. She has what I think is the more Roman nose of the bunch.
What is all this talk about noses? Well, it seems the nose is one of the always of dating cameos. If I understand correctly, earlier pre-mid 1800s cameos had what people are calling a Roman nose. I think they mean the more prominent, defined nose. Through the mid-Victorian era, the latter half of the nineteenth century, the nose became straight. In the twentieth century, the nose is referred to as a button nose. From when I was little, I was told I have a button nose and that the nurses at the hospital even nicknamed me “button”. So, I am a bit put off when references to the button nose are used rather scathing in commentary on cameos. (Really, so sites are crass. See the one referencing”something my cat dragged in”.) But, anyway. The tiny, rounded noses are a twentieth century thing.
I need to learn more about the carving lines, styles, depth and details of design to get a more personal understanding of cameos. I tend to like art Nuevo pieces when it comes to jewelry. This is a challenge for me.
More examples
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If I Had My Own Blue Box: 