I'm in an iron miner that hasnt had to blast and iron is harder than copper isnt it? -they just use excavators with or without ripper buckets and D8 or D9 ripping tractors or a hydraulic hammer (the most primitive method)

and whenever I visited a huge copper mine they were just using excavators also

any alloy bucket strengthened with titanium or whatever they use seems to work fine

I could hunt for a pic of a ripper bucket if you want