DA,
You're doing OK with the camera, a little more working with it and you will have totally sharp pictures, as is they are pretty good closeups with reasonable depth of field. I put my camera on a small tripod (the whole thing fits in ones hand), fiddle with books and stuff to get the subject within the range of the lens, press the the macro button, turn off the flash, set up a light, set the white balance and shoot several pictures till I have a good one. At times I will also use my remote control to totally eliminate shaking caused by pushing the shutter release button. You are also doing great with the detector! Gold rings, definitely first rate detecting!
AND, I just noticed your post says "some of the gold in the last two weeks"! If you think your pictures do not look good its likely because your eyes do not see properly from being smitten by at least two gold rings in one week and maybe more just out of the picture.