This ring has a purple stone is marked "925" and "CA" I went looking on the web & the site but was unable to find any information relating to hallmark of CA. Only able to find one more mention online of a piece with the same hallmark-- which notably had a similar "circle" design in the basket.http://i280.photobucket.com/albums/kk163/rubyglass7/another_ringwithCAhallmark_18kgp_ov.jpg
I assume it to be american, bought at an antique fair in chicago.
Can someone help identify?

my ring and CA hallmark

another view of ring
thanks
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