With some of my clad that I dug last year, I went out and bought some gold.
A 2 peso gold coin, a 1 gram gold bar, and a 5 gram gold bar.
I tested them as to the VDI on my 3 detectors a Whites IDX, a Whites M6 and a Garrett AT Pro.
Here are the results on the VDI.
2 peso gold coin- shows up as foil or nickel signal
IDX---5cent/pulltab/ring
M6--VDI #16 foil
AT PRO-- VDI# 50
1gram gold bar - -shows up as pulltab or ring
IDX---ring/pulltab
M6-- VDI # 37 pulltab
AT PRO-- VDI # 65
5 gram gold bar -- shows up as penny or dime
IDX--1 cent/10 cent
M6--VDI # 76 penny
AT PRO--VDI # 80