May not be the best for commercial purposes. Has some few drawbacks (list of possible identities somewhat inadequate). On highly refractive stones (high zircons, diamonds, etc.) sometimes has problem deciding what reading really is, i.e. I know the stone is zircon, not garnet or sphene, yet the PRIM II cannot seem to quite reach a zircon identification. Also, seems to be a better instrument in the first few hours of use...the longer time it is turned on, the wackier it seems to get. Still I'm glad I bought it as I was tired of turning my workspace into an EPA clean-up sit......
(Posted on 4/7/18)