Gerry and Dave.........I live on the east coast of Australia where 'bad ground' is never an issue. I don't use the Cibola on the beach, I have a PI that handles the wet sand.
I'm using the standard 9x8" concentric coil which pinpoints wonderfully. I may add the 5.75 later (for trashy areas), but for now the 8x9 is just fine.
For settings - I discriminate high with the knob on tab. Threshold at 3 o'clock, sensitivity about the same. Here in Oz those settings will easily pick up all the $1 and $2 coins, 50 cent coins, and all pre decimals expect for the tiny threepence piece. Will also get most silver and gold rings. I don't dig a lot of trash these days - bar the occassional screw cap. These settings will also find every damn obsolete 1c and 2c piece, as the Cibola hits hard on coppers!
Depending on the mood I'm in, I will drop the disc down to just above iron and hunt the smaller denomination 5, 10 & 20 cent decimals - I've learnt how to identify their tones amongst the rubbish. Took me a while, but now it's clear as day.
On good sites - such as above - I will supertune the machine to get more depth - and then I'll pick up the silver 3 pence bits.
