I had one and moved from the west coast recently. I wound up trading it off for a DFX. I found that the GMT is Very sensitive to small gold by understanding how it talked. Making sure it was properly ground balanced, and listen for the most faint repeatable signals. Being able to "pump" the coil and eliminate bad targets was huge. If you get a reading below 50-75 you should dig! The more you do, the faster you understand. I usually dug anything under 50 personally. Solid larger targets like rings, aluminum, copper will hit hard and sometimes may dissapear when pumping the coil too much. If its solid signal and repeatable, dig it. Gold is were you find it!!! At first I wanted to hear it blare at me, but just dug foil, etc. Once i learned to listen to what it was telling me, the faint, repeatable tone, I started finding gold. I have also read reviews were the GMT will out do the $4-5K machines in tailing piles. Also another feature I liked, was the black sand levels. We would walk perpendicular to the river and track the highest readings of the black sand. Then, move a few feet up or down stream and do it again. Plant flags at the highest reading in each area. You will then see the line to dig for the best chance of getting that Shiny metal, Gold! Seems like the Placer gold will accumulate on the inside of the line you have drawn. Get out the sluice and start digging.
My last advice would be, GB often, by pumping the coil, drop the power so the machine is stable. Do NOT try cranking it up and it will be alot more enjoyable. It may help to be slightly positive for smaller placer gold. Slow and low on the sweep. Listen for the very faint signal, trust the machine! Once you get the hang of it, it is recomended to crank it up to 10 and 10, it will go deeper and now that you understand what it is telling you, can be used this way and be very productive. Good luck out there,
Best regards,
Don
