{
  "type": "minecraft:sequence",
  "sequence": [
    "minecraft:bedrock_floor",
    "minecraft:overworld/copper_ore_vein",
    "minecraft:overworld/iron_ore_vein",
    {
      "type": "minecraft:condition",
      "if_true": {
        "type": "minecraft:above_preliminary_surface"
      },
      "then_run": "minecraft:overworld/surface"
    },
    "minecraft:overworld/underground"
  ]
}