I agree - I'm afraid this is a serious problem these days.
The "yellow turquoise" issue is another confusing one. I think a lot of it is powder of some stone (turquoise? jasper? who knows!) essentially glued together with a lot of binders.
When I first worked with "yellow turquoise," I created a sterling linked necklace and then dropped it into my rock tumbler, which I use to polish up the silver. When it came out, the finish was gone on the stones - they were pale and grainy looking, with no gloss left all! That should not happen with a real gemstone.
Then recently, I had a customer return a strung "yellow turquoise" necklace to me to be repaired (the silk string had broken) - and somehow, all the "yellow turquoise" stones had turned BROWN.
I now think the binder in the beads must have cooked in an ex-ray machine or something in transit - bizarre!
So, needless to say - I'm "off" the yellow turquoise completely, even though I'm OK with the glass "quartzes" as long as they're recognized as glass.
I think corruption occurs in the imported supply lines when something suddenly becomes very trendy. Overseas manufacturers seem to rush to find ways to produce look-alikes extremely cheaply - but they're NOT being held accountable to disclose what these materials really are.
As middle-level suppliers and jewelry designers, we really have to keep our guards up!
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