At least I try to, anyway, and as was suggested I always like to run my Sensitivity/Gain as high as possible. Just below or at the fringe of instability.
I also like to know about ALL metal in the ground, including most iron, because if I hear the iron targets there I can slowly work around them in case they are close enough to mask a good target. Sometimes I hunt with NO discrimination, and other times I hunt with it at the default setting of '10'. Now, an exception to this is when the site is terribly littered with iron nails and, in that case, I use just enough discrimination to reject the nails. That's often about 21-22.
Naturally, finding jewelry, especially gold in nature, is the challenge because due to the lower-conductivity and the vast array of sizes and shapes, it can read anywhere on the VDI range from '40' on up. I use the reference to '40', the break-point for ferrous/non-ferrous with caution because I have found some small thin gold chains and other thin gold that hit right at that mark or slightly into the upper ferrous range.
Smaller and thinner sterling silver jewelry can read down lower from where you anticipate silver coins. Finding good jewelry calls for simply listening for a potentially good audio hit, making a quick glance at the VDI to make sure it isn't probable iron, pinpointing and recovery. Visual target ID, regardless of the make or model or cost of the detector, is never going to be perfect.
If you are 'Coin Hunting' and want to recover ONLY the most probable coin targets present, you can rely on the Target ID segment, or a more specific VDI (Visual Discrimination Indicator) numeric read-out, and recover just those targets. Naturally, you will then only get the jewelry that produces a mimic of a coin response.
So, with a high Sensitivity setting and a low Discrimination setting, with any detector, it would help locate the most coins and jewelry present at any site. the one feature that might help is a Tone ID function. With the T2 you have several options, but my favorites are '2+' or either '3' or '4' Tone ID. Note that the '3' or '4' tone options are only that if you are accepting some iron-range with the Discrimination (below '40').
I most often hunt a site in '2+' if there is iron. If a site is mostly iron-free, then I will use the default '1' or maybe '1+' and just enjoy a solid audio response from everything. If there is some iron present, then I like '2+' and a lower Discriminate level so that I can hear the Iron and hear the non-iron. I enjoy that.
When I do want a mix of audio tones, the '3' Tone ID feature is fine. A Lower tone for Iron, a Medium tone for foil through screw caps and zinc cents, and a High tone for the higher-conductive coins (most copper pennies and dime, quarters, etc.) as well as the US nickel coin. The T2 was designed to lump the narrow VDI range 5
