I found a company online called stamboul jewellery who are apparently based in Turkey. They make some amazing looking pieces, mostly silver rings, for a very reasonable price. They have a website but seem to mostly sell on ebay which is where I found them.
The question is, given how easy it is to buy fake reviews and the amount of fake silver coins out there, how can you be sure that the nice shiny thing you bought of a foreign company on ebay is legit? There's plenty of big names that make fashion jewellery and if you look at the mens rings you'll often see in the small print that they're silver plated brass or similar.
I know I could send a purchase to an assay office here in the UK but I expect that'd probably cost at least as much as the cost of the piece. I know some jewellers have XRF machines, would I be able to go to a larger jewellers and ask them to test an item for a small fee? What about those companies which offer to buy silver or gold? What's the best option here?