{
  "type": "minecraft:spring_feature",
  "state": {
    "id": "minecraft:lava",
    "properties": {
      "falling": "true"
    }
  },
  "valid_blocks": [
    "minecraft:netherrack",
    "minecraft:soul_sand",
    "minecraft:gravel",
    "minecraft:magma_block",
    "minecraft:blackstone"
  ]
}