Hi David,
Funny you should ask because I have been testing the Beachscan equipped with an 11" coil to see if it can be used as a nugget hunting machine. Sometime in the future, I hope to try the same machine with an 8" coil also, but I would expect the results to be about the same.
The answer to your question as to whether the Beachscan can be used to hunt for gold nuggets, the answer is yes. Also, the Beachscan goes quite deep. In fact, I just tested this unit against one of the high priced units and as for depth capabilites on three different sized burried nuggets, a 1 oz nugget, a 1/4 oz and one that is about a pennyweight. The results were the Beachscan depth capabilities were quite close.
I have also taken the Beachscan to a couple of gold producing locations here in Colorado just for testing purposes to see what problems one might encounter.
Overall, the operation in gold producing ares will depend upon the ground conditions. In all areas I tested, there was little if any response to hotrocks. Many of these type of rocks that give a VLF fits are ignored by the Beachscan.
Depending upon the different ground conditions, some areas will produce very little if any ground response if the coil can be bobbed up and down, while in other areas, there will be some noticeable audio variations when the coil is raised and lowered or raised to go over a rock or vegetation.
As I said before, the Beachscan will ignore most typical hotrocks but it will detect basalt as well as the meteorites I have been finding in Gold Basin, AZ. Although I haven't tried the Beachscan in AZ, I did want to see how the meteorites responded so I ran a controlled test at home using a couple of different sized meteorites to see how well it worked. On the meteorites, the sensitivity isn't quite up to par with a good VLF gold hunting machine, but it does work ok.
As for gold nuggets, can get a reasonable signal from a 10 grain nugget, and a very weak signal from some down to 5 to 7 grains. This depends upon up the shape.
The key to using the Beachscan is to make sure to keep the Frequency control at minimum, use good earphones, and keep the threshold up to the point where there is a slight threshold, or in really bad ground, just to the point where there is just a little or right at the pont where there is no threshold for maximum depth.
One other little point, I love the open center coil for nugget hunting purposes. During my testing, I would find small pieces of lead and other parts of rifle bullets and found I could grab a handful of dirt, pass my hand through the coil to see if I had the target in my hand, and repeat the process until I had the target located. Then it was just the matter of separating the target from the remaining dirt in my hand.
Reg
