I always thought a jeweler’s loupe was some special kind of optical device (obviously deep thinking hadn’t gone into this) that allowed the user to tell whether a gem was fake, as well as the quality of the gem if it was real.
Now, in my advanced years, I have begun using loupes in my fountain pen hobby, and they really are just magnifiers, maybe 10x or even less. So how does such a magnifier help the jeweler tell if a jewel is fake? Do they look at the edges of the facets to see how sharp they are, or the facets themselves to see how they reflect the light?
Unfortunately, I don’t own any real jewels to look at under magnification.
It’s just a powerful magnifier.
So, that allows a jeweler to inspect a “gem” - if it’s flawless, it’s either a fake, or a very, very valuable specimen. If the jeweler sees inclusions and flaws in a diamond, he can be pretty sure it’s not zirconia.
So if you get to the point where there are no flaws, what’s next? Something besides using a loupe to determine whether it’s junk or priceless?
I mentioned my pen hobby above. I recently acquired a Soviet-era Soyuz pen, it has a cheap feeling plastic body modeled on a Parker 51, and a completely over the top gaudy and heavy metal cap that is gold-colored (looks more like brass to me) and it has a gaudy red “jewel” at the top. Usually pen “jewels” are just decorative elements made of plastic or metal, but this is, I believe, intended to look like a ruby. When I look at it through the loupe I can see that the facets are not smooth and the edges are not sharp, there are tiny scratches and chips, leading me to strongly suspect that it is made of colored glass. Shall I spare myself the embarrassment of going to a jeweler? Is this a definitive test?
There are heat conductivity testers and refractive index testers that can be used to validate the authenticity of a gem.
As for your “Ruby” - see if it fluoresces under UV. If not, it’s fake. Even if it does, that’s not a definitive test, but it’s one step.
The trope probably started with people testing to see if a jewel was a bit of cheap costume jewelry made out of glass or plastic. The advent of zirconias and the like changed the game.
As has been already mentioned, the loupe is really just a tool to quickly evaluate a gem for inclusions, cavities, cloudiness, off colors and poor cuts. There are better specialized tools to test all these things in a more lab-like setting, but for quick and dirty work a loupe is useful.
Fastest way to reliably identify a CZ is by weighing it, and to be doubly sure you can test it’s conductivity.
Thanks for that link, it was very interesting reading.
I’m beginning to think, however, that my “ruby” is possibly amethyst, it has that violet coloring to it, and it doesn’t seem to be paste, and it does have some sparkle, and a relatively cheap semi-precious stone is something that might actually have been put into a fancy pen cap like this, that was probably gold plated at one time.