G'day
It could be a just highly mineralised spot or a metal target, firstly no matter what machine you are using go through your ground balancing procedure to be sure the machine is properly balanced and tuned, do it in a spot away from the target area to be sure, but I repeat never ever walk away from anything like that unless you are sure what it is either way, you never know it could be the cap of a gold bearing reef, a large nugget,or just crap, but in light of the fact you say that you have found some pieces nearby makes that a likely scenario for it to be gold also, the only way to find out is to dig and be sure what it is, better to be wrong than right, the worst possible thing would be to walk away from it only to find out later and hearing about someone else scoring big there after finding the disturbed ground you have left behind, as I have found many nuggets in old dig holes over the years. :lol:
Many years ago when I was new to the game I came across a similar thing and walked away from it as I did not know any better, but even after all these years I still think about where that spot was and what it possibly could have been, I have made several attempts to find the place again and looked in several locations that have looked familiar,but I am only able to go by memory only as I did not have a Gps back then to mark it as I would do now, and as I have not been able to locate it so its either still there or someone else has dug it out, so unless you find out either way the memory might stay with you for a bit. :awful:
cheers
stayyerAU