As a conversation starter ... what are the names (and taglines) of some of your competitors? What are some jewelry business names that you admire, perhaps in different regions or countries? Where are you city/state/region/country?

Glitz (Jewelry)
Modern Glamour (Jewelry)

If you want a really effective name and tagline, think of what your best clients like - apart from jewelry. This sort of thing will then fit jewelry in with their current likes.

Steve is right, what you can also do is work out their advertising pitch on a spreadsheet - and you can go for the areas that aren't served. If you bring those results back to us, you will get some names that will really rock!

In the mean time

Accessories Anonymous - - - For the seriously addicted.
Modern Heist - - - Grab your jewels here.
Dangerous Glitz - - - Be warned our stuff is nice.

Moriarty xx

Sorry, but you're not in the "jewelry business." Given the items you hope to sell, you're in the fashion accessory business, and any name you select ought to reflect the depth and breadth of the the lines you're selling.