Thanks for your praise! I'm most proud of the animated 2D elements myself!
I thought about the beeping rate increasing when close to gold for initial design early on, but in playtesting I figured it was more potentially entertaining to put players in the dark and have them deduce things on their own based on where they've been. Some gold also spawns on top of the mines which would have screwed with the beeping code a bit, so I decided to simplify things with clearer, more binary distinctions:
The gold is made to spawn within an inner circle around the mine and that inner circle is what sets off the slower beep as opposed to the gold itself. The idea is that players know they're in the general vicinity of gold and the land mine is also setting it off to a degree which is intended to up the danger factor.