GemtoneGemtone Deluxe Jeweler's Diamond & Gemstone Analyzer Tester for Diamonds Moissanites Stones Lab-Created Simulants with Stone Gauge

It works, but it is not a plug-and-play device. You need to tinker with it and become accustomed to how it functions. Be prepared to invest some time learning how to use it. I would not characterize this as "deluxe." However, it is an accurate and functioning diamond tester for a decent price. Recommended.

Learning to identify different stones

I couldn’t get it to work

So there is a learning curve with this so be ready to play around with it, get items you know are CZ, Diamond, Moissanite and more and go from there. I'm luck enough my dad had a tester when I was a kid and taught me how to use it that when I read the instructions everything started coming back to me. It's well made just be ready to practice and play with it for a bit, don't jump right into take your time and you'll be a pro in no time.

Pay attention to the instructions - how to hold it, how damp your finger is, and where the stone is all make a difference. If you pay attention to the instructions this works perfectly. I've used it to test multiple stones that I already knew were genuine or created in multiple different ways and it accurately indicated each one. It is easy to use and reads pretty easily.Overall this is a good price for a well designed and easy to use gem tester.