"China" gets a bad name because of eBay, Alibaba, etc. sales, but without a doubt, there are dozens of factories that manufacture whatever you want or need, with most showing and selling at the major trade centers like in Yiwi. And yes, with the reproductions there as well, you can compare side to side real from fake.
Meanwhile, that ring machine does not care what metal is put into it and why you will see plated pot metal with a 925 stamp. I.E. it will make 925 rings, but often using worn out dies not suitable for quality. In fact, the auction photo will often be of the original; beautiful, shiny, smooth finish, etc. .... but not what you receive.
We will often hear you get what you pay for, but that is a relevance issue to the selling platform. Who goes to an auction to pay retail? You can buy name brand tools on eBay for less than half (or less) of retail, so should you expect junk? Sadly, with imported jewelry, you probably should. It is a numbers game. When 95 to 98% of ignorant buyers leave positive feedback, there is profit in fraud and the seller will call it whatever will sell. Have too many legitimate returns and eBay will slap your hand or worse.
For us, the problem is time and time is money in a business. After 40 years, we can spot most imported fakes, most plated item across the room. We do buy 'shorts' and samples on eBay as a search for new suppliers, but to be honest, have yet to obtain real 925 items from China or now India and worse, the same items are now being sold by US sellers. Fact is, they are getting better at avoiding detection by using pot metal of zinc and aluminum that is non-magnetic, but still silver when cut in half. Of course they fail the acid test or better and faster, the xlr analysis.... but not everyone has a $15,000 piece of equipment laying around.
People have different body chemistries. For the novice, a magnet will seldom work for rings or bracelets. The green finger is from the copper bleeding through on plated, but the black ring finger can be from real silver, or the now plated aluminum and zinc bleeding through, or from nickel, cadmium, etc. in the plating, or etc. It is buyer beware and you should be aware to the best of your abilities.
Just look at the finish of imports and if small bubbles where the plating did not adhere, or if the finish appears like it was brushed on, it is poorly plated whatever. That does not work so well for older costume jewelry because gold was $35 ounce and Silver far less, the plating or more often filled was government regulated and very high quality that lasted through time; also required a valid stamp for content. The industry policed itself and not worth the risk when the metals were very cheap in comparison to today.
That said, with 925 Silver about $14 a Troy ounce that will make a lot of rings, you will not find US manufactured fake 925 items... only imports. And that ultra shiny finish, albeit rough and or bubbled inside the ring is not silver, but rather it is zinc that is increasingly blended with cadmium, a known carcinogenic.
As far as stones, don't expect anything real from mass manufactured imports. And don't confuse Cubic Zircon with real natural Zircon that is more rare than diamonds. Oddly enough, companies like Zales used to use natural Zircons in place of diamonds because they were cheap. Not so today, so learn about Zircon when in the thrift stores or estate auctions. And learn how to do a cheap specific gravity test to identify stones, or at least eliminate most of the fakes in conjunction with a hardness tester.
That said, with the exception of CZ's and Moissanite's, we have yet to purchase one real stone as advertised on the auctions from China or India. And even those are subject to being mis-graded as represented. It is what it is.
Always happy to help when I have some free time, enjoy collecting...
