I sell jewellery, so may be able to help a bit with that...
First and foremost, jewellery is very much a visual category - by which I mean presentation is important. Photos don't need to look like they were taken by a pro in a studio (mine certainly don't 
), but they do need to be clear, crisp, bright and show detail, as well as (preferably) show them in the right scale, which is tricky, but do-able with multiple pics (eg use a common coin, a matchstick, or show them in the palm of the hand to give people a visual idea of sizes, and if something looks a lot bigger in a gallery pic, use keywords in the title like petite, small or tiny and/or exact measurements).
My top photography tips for jewellery (as I prefer, so what works for me may not always work for someone else), clean, non-busy backgrounds that have a decent amount of contrast with the item being photographed (this is primarily because I suck at composing pictures any other way - props etc look awful in my photos 
), natural light, but not direct sunlight (flash is not generally recommended), use the macro setting on digital cameras to get decent close-ups that aren't blurry or 'noisy' (noise gives images a kind of static-y effect), take images from slightly further away or wider angles to give you some space to edit and crop nicely, and learn to use some standard image editing functions in a program like Windows Gallery if you have a PC, which will let you adjust things like brightness, reduce shadows, change colour temperature, contrast etc. (My images are not very good at all until I've adjusted a few things).
Research the generic style or design names for certain pieces so that you can use your keywords more effectively - the drop earrings could also be described as chain / tassel / beaded / dangle earrings, then describe everything that the buyer can't tell from looking at the photos - all materials used, sizes / measurements, if non-precious metals whether they're free of common elements buyers avoid like lead and nickel (the description doesn't have to be lengthy, just informative).
Jewellery is a saturated category, so IMHO, and in my experience, being cheap isn't going to get you anywhere near as far as being different, and there are a lot of little ways a seller can be different - some general ways may be range (diverse, off-beat, catering to a sub-culture, etc), other little touches like packaging and so on.
