I ordered a jeweller's loupe for the website because I use mine often when looking at rocks. I ordered this one on a keychain because what a brilliant idea!?! I am away to put my own jewelry loupe onto a keyring. I am getting blinder all the time.
 
I love this. sturdy, easy to open, makes small print bigger, shows me the surface of crystals and mineral specimens. Excellent when checking tiny crystal structures. I used this on a bit of hematite in the photos so you could see the effect. I hope it worked.
 
Anyway. This is where you buy a good quality jeweler's loupe so you can better examine rock inclusions.