Very interesting what you said:
Jewelry gold (9K-18K) is alloyed with copper, tin, manganese and a few other metals. The lower the carat, the LESS gold that is in the item and the more of these others. This actually moves golds natural conductivity higher up the range - offsetting somewhat the benefits of a higher frequency. As it turns out, the optimum frequency for general purpose detectors is between 12 and 15khz - just what the Vaquero uses!
First let me say I dont believe what dahut says about gold is correct, the part you have quoted in this thread. I believe golds conductivity is just below copper and copper is just under silver, and silver is the top of the list so any metals added to it should lower its conductivity,not raise it.
Here is the scale of electrical conductivity for various metals, pertinent to us as detectorists.
Copper is the standard, at a scale value of 100
Aluminum 59
Brass 28
Chromium 55
Copper:
Hard drawn 89.5
Annealed 100
Gold 65
Iron:
Pure 17.7
Cast 2-12
Wrought 11.4
Lead 7
Nickel 12-16
Nickel silver 5.3(18%)
Phosphor bronze 36
Platinum 15
Silver 106
Steel 3-15
Tin 13
Titanium 5
Tungsten 28.9
Zinc 28.2
Bsed only on these numbers, I may have had it reversed. Aluminum @ 59 and gold @ 65, places them pretty firmly in the middle - but gold IS slightly higher than aluminum, although not by much.
Alloyed gold may not be the cut and dried thing that this suggests however. There are factors at work that can affect it's respnse, which are not related to the electrical characteristics of pure gold. At least enough so that sweeping declarations about it's behavior are fallible, either way.
Regardless of its composition, it doesn't move much on the scale.
But one thing seems pretty sure - we're right back to the tried and true motto of every successful gold jewelry hunter:
"If It Looks Like Foil, A Nickel or A Pulltab, DIG IT!"
I think maybe I had better watch just where I put my foot in the future - or it may end up in my mouth!