What numbers on mineralized ground ?

[SWMO Mark]

I have a AT GOLD and was wondering what ground balance numbers were considered bad mineralized ground. In my area, I usually balance between 39-42. Thanks, Mark

 

[MikeLab]

It's not always cut and dried. Sometimes ground is a combination of ferrous (mineralized) and salt (conductive). So sometimes the ground balance right near the ground is different. So instead of pumping the coil eight inches high, you only pump to the level where the ground changes, sometimes only one inch high. One guy said even less. The auto ground balance is just not quick enough to handle this so manual works better in this type of ground. There is a chart in the instruction manual but it doesn't address this.

 

[Billyjoe42]

Using Auto GB, I notice the ground value number increases with successive pumps, usually stopping (& holding) about 12 digits above the number shown on first pump. I don't understand this, but hope is normal.

 

[William-NM]

Hi Mark, Here in NM, my GB is around 83, up to low 90s if I head up toward Fierro (Iron mining in the area). I sometimes manually knock it down to 75 with the hope of hitting Silver a little harder and the Iron a bit less. 39-42 sounds mild to me.

 

[Southwind]

Here in Dodge City my AT Pro always GB's in the low 90's.

 

[SWMO Mark]

Thanks for all the info. The manual never really addresses my question, so I have always wondered where my ground balance was running. Mark

 

[MikeLab]

If it's not in the Pro manual look on the AT Gold instruction manual for the chart. It's on the Garrett website. What I see is you are in somewhat conductive ground and you might not be getting a good ground balance by pumping it high in the air. I'm probably not explaining it very well, but try to use manual balance and just pump an inch or so into the air. You can always bury a small target and then adjust GB up or down until you get the best signal.

 

[88junior]

In my Georgia mineralized soil mine usually ground balances from 37 to 51 on my AT Gold when I had my AT-Pro it would ground balance out between 80-87