I've searched for this mark and haven't found it yet. I'm assuming it is American but it may not be. I'm not even sure how to describe the mark. Is it a W or a candelabra?
That is James Avery's mark. With that, it's pretty easy to find information about the company online. Also, here's a link to another post about this jewelry maker: viewtopic.php?f=27&t=22194&p=52487&hilit=Avery#p52487