Bronzium is the weakest ore. It's really slow, and it's brown-orange. It can be found everywhere, including the surface. One bronzium ore sells for 33 bronze. This is the worst ore, so don't have these for more than 5 mining sessions. Bronzium is Black Tier, and it's really useless, so after you've played atleast 40 minutes of a singleplayer world, bronzium will probably be trash.