This post was a response buried deep in a thread on the Equinox Forum, but got long enough on a subject I think about a lot, that it deserved its own thread. Here you go.
I find the whole George Payne way of conceptualizing things to be rather out of date myself. That was back in the day when only one thing mattered - detecting coins. Silver coins in particular. So he was looking at frequency, and most importantly, coin size targets.
If you do that, fix target size, you get the false i
Excellent post, PimentoUK. I will make one small correction -- our USA 5 cent 'nickels' are 75% Cu. I think that drives home your point even more. As a sidelight, during WWII they changed the comp to 56% Cu, 35% Ag, 9% Mn (= manganese). It's no coincidence that these Warnicks, when not adversely affected by leaching, give the same (or very close) dTID (at least on my ML Equinox) as the standard composition. There was an intense(?) study done to match both the conductivity and density becaus