gpz7000 on big targets

hello everybody, and first excuse me for my bad english but I am french. I plan to buy a gpz7000 with 19' coil (mono/DD coil) not to find gold (unfortunatly in france there are not nugget ) but to specific tresure hunting. before to buy the gpz7000 I would like to ask you something : for me it won't be to try to detect litle targets but big targets. so my question is : do you have an idea of the maximum rough detection depth of gpz7000 with 19' coil for a metalic target of 4 inches diameter in normal soil (in france ground is not as mineralised as australian ground) ? it's just to have an rough idea, I know well that maximum depth mean nothing, but at your idea is it close to 30 inches, 40 inches, 50 inches, 60 inches ?
thank you for your answers.

You would probably be better of with a GPX 4800.

They were made for the kind of hunting you intend doing.

GPZhunter wrote:You would probably be better of with a GPX 4800.

They were made for the kind of hunting you intend doing.

With a 22" DD Coil
http://www.coiltek.com.au/coils/goldstalker/22-goldstalker/

Agreed,
No need to spend 10 grand to do what you want to do.
How deep do you want to be able to detect a 4 x 4 inch bit of metal?

Good advice coming from all members here Albert. The GPZ 7000 is first & foremost designed for gold nugget hunting, in areas of high mineralization. You'll find little advantage on depth over metallic targets 4" X 4" inches wide & above, using a 7000/19 inch coil, as compared to a GPX series or GPX 4800 detector, using an 18 or 20 inch round mono coil, over low/very low mineralized ground. In benign or quite ground conditions, some top of the line VLF detectors, give PI units a run for their money.

Cheers Kon.