View Single Post
  #18  
Old 05-19-2012, 11:02 PM
HarveyH48 HarveyH48 is offline
Elite Member
 
Join Date: May 2011
Posts: 3,710
Default

Considering that there is something like 15 or 16 different kinds of iron oxide (rust), which can flake off, or leach into the surrounding soil. It really isn't surprising that old nails come up as different metals. The machine isn't detecting the actual metal, just an electromagnetic signal, eddy currents, and makes a calculated guess, based on the strength and duration.

I've pretty much dug a ll the good signals out of my backyard, and down to digging mixed and subtle signals. Pretty much just digging nails lately, but did get a corroded zinc this morning.
Reply With Quote