One of the local metal detector dealers in my town recommended that I take my finds to Gem State Gold and Silver in Boise. The owner has a Spectro-Midex machine that can tell you exactly what type of metal you have. One of my rings measured 14.37 kt and the percentage of gold was 59.86. So he paid me for the 14.37 kt instead of just 14kt. He told me that the machine cost over $75 grand. It also shows the percentage of other metals in the ring. Needless to say I was quite impressed and feel like I got the best price for my finds. He pays about 75% of the actual value. He also gave me a printout of the machine findings. The machine uses X-Rays to determine what metals are present. Has anyone else heard of this?