Yes I have a nice assortment. I even bought a gem microscope. I can’t tell you how much fun that has been, inclusions are fascinating.
I think the best items are a good pair of gem tweezers (if you are viewing loose gems) a good loupe (x20 is better) a UV light and a dichroscope.
Refractometers aren’t all that easy to use and it needs to be a loose gem. Likewise calculating Specific gravity (you need a loose gem).
I also have a Presidum gem tester. This is only really useful for quickly IDing CZ. I buy at auction (in person ones) and often times things are described as “white stone” i check to see if they are glass/CZ or something else.
The big problem is identifying between natural and lab grown material. Lab grown rubies fluoresce like natural ones, they have the same specific gravity, same refractive index, the only difference is the inclusions.
When it comes to treatments, a good loupe and knowing what to look for can help you know if it’s unheated or heated or glass filled but you can’t ID beryllium diffusion with any “at home test”.
so on the surface it seems fairly straightforward but once you start getting into the nuances, it becoming more complicated. And value varies significantly when it comes to treatments. Heat only is one value, heat with evidence of residues is another value and heat with diffusion is another value.
however, it’s a lot of fun learning.