For what it's worth, you might want to work a little harder to convince people that they're buying top quality jewellery from a legitimate retailer.
I'd definitely revise the "About Jewellery" page. Firstly, retitle it "About Our Jewellery". Use it to explain your expertise in selecting only the finest jewellery and to list your qualifications as an expert goldsmith. You wan't people to part with their hard-earned money, you'll have to gain their trust and respect.
Traditionally, your target market wants a brick and mortar location where they can physically pick up and touch items. They want to look deep into a diamond and see their reflection in the gold or silver.
Your pages look great, the site runs fine and you seem to have all the relevant data they could ever want about your products, but you might want to consider revising the way products are displayed. This is quite likely to be considerably expensive to implement, but I feel this is the one single biggest obstacle you face that would result in more conversions.
This site will explain what I'm talking about. Check out the 360 image displays.
photo-mojo - 360 degree product photography and packshots
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