The issue of gold, when it comes to nugget hunting, as per the needing of a specialized machine for that, has nothing at all to do with gold in the forms of rings and coins. The reason you'll often hear about gold nugget specialty detectors, is that gold ... in the natural form of nuggets, are rarely grain-of-rice sized or larger. Guys who go after naturally occuring nuggets, are usually getting them in pinhead sized (which add up over time). To find a nugget fingernail sized, etc.... is super rare.
Thus nugget machines are designed, from the ground up, to be super sensitive to teeennnssssy things. This is exactly the opposite of a coin/jewelry hunter's mindset, because perhaps he DOESN'T want to hear every push-pin, birdshot, and staple in the ground

Ironically, a nugget machine that might get a pin-head sized nugget down to 2", may only get a coin to 8". While a coin machine won't pick up the pin-head at all, yet be able to get the coin to 10" And nugget machines/coils may have poor discrimination in their inherent engineering/designing, because they don't need disc. If they do have some sort of rudimentary iron disc, perhaps it's only effective in the first several inches. Beyond that, everything sounds the same. No problem for a nugget guy though, as he's in it for insane sensitivity, at whatever cost, for the smaallleest of things.
The Explorer does fine on coin and jewelry sized items, of any composition (gold, silver, copper, etc....). Of course, you're not going to find teensy gold earing studs with it. For that, you would need a nugget machine.
And within the various coin/jewelry machines, there are admittedly some that do better on smaller low conductor items than an explorer. But the trade-off is, you might not have as much depth as a power-house machine like the explorer, or perhaps you might start to falter in mineralization, etc.....