TheKhopesh, where did you seen 20 arrowheads per single nugget? The ratio is 1:1! Maybe screenshot is a bit confusing because of items in input slots, but arrowheads are consumed one by one, producing 1 nugget each.

This mod will not receive any updates; instead, I will add recipes to smelt useless stuff to TinyTweaks mod.

20 arrowheads per single nugget?
That's pretty steep. Given an ingot is 20 nuggets and makes 9 arrowheads, you'd think each head would be worth a nugget (it would technically give a hair more, but factoring in hammer durability, it'd take longer to exploit it enough to get another ingot than it would to go out and mine surface copper nodes for +50x as much copper in the same time frame).

Perhaps next version will be integrated in my TinyTweaks mod instead of being standalone. Not sure when, because Vintage Story isn't my primary modding game.

Thanx, OmegaHaxors, I will change this both to support hammer and to not check game version next time! And perhaps, more metallic items available from panning will be possible to smelt for something usefull.

Rocks may be either expensive or just a garbage depending on biome. The last world I played in had a spawn in a mountain biome with lots of boulders, stones was really abundant.

add this after the final } to add hammer support

,
{
"ingredientPattern": "H,A",
"ingredients": {
"H": { type: "item", code: "game:hammer-*", isTool: true, toolDurabilityCost: 1 },
"A": {"type": "item","code": "game:arrowhead-copper"}
},
"shapeless": true,"width": 1,"height": 2,
"output": {"type": "item","code": "game:metalbit-copper","quantity": 1}
}

It won't load on older versions since the JSON hard-codes the current version requirement.
You can fix this by deleting the dependancy tag.

For the rock recipe you should increase the stack size of the arrows and yeild of fragments to 20, it's kind of expensive on rocks at a 1:1 ratio.

Perhaps should work with (much) earlier versions too, but tested on 1.17.8 only.