public static void smeltBlockInWorld(World world, int posX, int posY, int posZ) {
    FurnaceRecipes recipes = FurnaceRecipes.smelting();

    Block block = Block.blocksList[world.getBlockId(posX, posY, posZ)];
    if (block == null) {
      return;
    }

    int meta = world.getBlockMetadata(posX, posY, posZ);

    ItemStack smeltedStack = recipes.getSmeltingResult(new ItemStack(block, 1, meta));
    if (smeltedStack != null && smeltedStack.getItem() instanceof ItemBlock) {
      world.setBlock(posX, posY, posZ, smeltedStack.itemID, smeltedStack.getItemDamage(), 3);
    }
  }