onEvent('worldgen.add', event => {
  
  event.addOre(ore => {
    ore.block = 'kubejs:fossilised_urn' // Block ID (Use [] syntax for properties)
    ore.spawnsIn.blacklist = false // Inverts spawn whitelist
    ore.spawnsIn.values = [ // List of valid block IDs or tags that the ore can spawn in
      '#minecraft:base_stone_overworld' // Default behavior - ores spawn in all stone types
    ]
    
    ore.biomes.blacklist = true // Inverts biome whitelist
    ore.biomes.values = [ // Biomes this ore can spawn in
      '#nether' // OR #category, see list of categories below
    ]
    
    ore.clusterMinSize = 1 // Min blocks per cluster (currently ignored, will be implemented later, it's always 1)
    ore.clusterMaxSize = 2 // Max blocks per cluster
    ore.clusterCount = 4 // Clusters per chunk
    ore.minHeight = 4 // Min Y ore spawns in
    ore.maxHeight = 64 // Max Y ore spawns in
    ore.squared = true // Adds random value to X and Z between 0 and 16. Recommended to be true
  })
})


