When the wishbone first starts going off, you're still pretty far, so the BPM is really slow. So slow that I never just stayed in one spot listening to it. When the pitch went up, I thought I was getting warmer. When pitch went down, colder. So I kept moving, and the pitch went up and down such that I'd try to find the highest pitch I could, and start digging.

The pitch goes up and down even if you don't move. It has nothing to do with anything. Doh. BPM. Got it. Found the silver no problem...

Take out your Stagbreaker or Iron Sledge; smack the ground.

If you're not near any Obsidian, you will see "Too Hard".. and that's how you know Silver is nearby.

I sequence-broke and went to the Mountain before even beating Bonemass.. ended with me yeeting carts full of Silver off of said Mountain to craft everything my greedy viking hands could craft.

Anyways, beware the strange rock formations, for these are actually Stone Golems and they hit very hard. There are two types, also: pointy bois and smashy bois. Best way to fight them, if you have trouble parrying them, is to just hop up on a rock where they can't get you and hit them over and over with the Iron Sledge.

There is not only silver in mountains
The wishbone works with buried tombs too ( where are some big stones and a skeleton resting, sometimes a chest ) and makes a little bugy in that zone because dont stop even if you make a while crater, sometimes its fix reloging

You can test the wishbone also in Meadows areas to spare your frost mead.
Ther are somtimes circular arranged stone formations where you can find a buried chest.
Test there, how intensiv the beeping can be.
I had at the beginning also no clue if the beeping is intense enough to indicate that i am at the right spot.

If the mountain range is not large enough or high enough it will not have silver in it. Silver is usually at and above the elevation you find obsidian. Start at the very top and search there first.

Regarding the tempo of the beep you want it is about 105 to 107 beats per minute. I alt-tab out and use a online metronome set to 106. When the game and metronome are in sync you are right on top of it. Happy hunting!

you need to find the sweet spot when it keeps beeping rapidly, then just dig down a little in few spots until you hit silver.