Hey Jerry, I don't think you lost your Iron Mask by going into Prospecting mode. I think you lost it when you went into Beach GB while in Prospecting mode. The X-70 is set default to tracking GB when the Prospecting mode is applied. When you then implement Beach GB, the tracking goes away. I found that when you are in Prospecting mode with Beach GB, AND if you have that zero on the screen, simply press the GB button again and it will display the GB level. You can then adjust the GB with the +/- pads. And, if you toggle back and forth by pressing the GB button, you will go from the GB reading (which you can adjust) to that pesky zero. Over and over again!!!
To check the level of the Iron Mask, I think you may have to temporarliy take it out of Beach GB mode. After you do that, pressing the GB button will toggle you back and forth from Iron Mask setting to the GB setting. And you can adjust either with the +/- buttons from there.
(thinking out loud)
To be honest, I don't know what the Zero represents. The only discrimination in Prospecting mode is the Iron Mask. I can't think that switching to Beach GB while in Prospecting mode would nulify the Iron Mask setting, making it zero? Especially when you can toggle out of Beach and the IM setting is still there. But, I suppose we could prove or disprove that by testing with some various iron targets. If they are rejected when you are not in Beach and can see the IM setting... then you switch to Beach and they are accepted, it must be actually resetting back to zero in the Beach mode. HHHMMMMMM Got any iron laying around? HH Randy