Hi Bigjohn ! I get what you are saying
The really good synthetics are hard to tell by the naked eye. I think I can tell many specimens by the eye, but that is not always the case of course, there are some very good lab specimens once and a while.
With these really high quality lab created stones ( and they would have to be good quality because many you could tell with enough practice ) you would have to be a professional, and most likely need sensitive equipment to get an accurate result. I was just saying that a real professional does have some way of finding this out, but yeah there is some really good lab specimens that would fool most if not all, and have no way to tell without a really good pro with pro tools. There is always a way to identify with the right lab/gemologist. Honestly I am not trying to argue with you, but from all my research in the matter, there is always some way of finding this information out, albeit not always easy or readily available. And of course this wouldn't be possible to do when you are shopping for a stone at a market or online.
So maybe we could meet in the middle and say something like: Realistically not distinguishable but technically identifiable
I still think I can tell over 90 % of them with my eyes, and I think you probably could too if you really thought about it, and thought of what to look for.
If you're really in doubt, I wouldn't buy the item. There is a lot of scammers and not worth the risk if you don't really know your source. I would like to think your blue sapphire was real, but then again I would like to think most people are honest. I think synthetics should be banned. If you can't afford a sapphire or ruby pick another beautiful stone that might be more plentiful like a garnet or something. Ruins it for everyone else, all this fake stuff on the market
If you can't afford a Rolex, don't buy a " Rolox ", buy the Timex, it's not pretending to be a Rolex, but it's still a good watch.