Board Thread:Wiki/Forum Technical Support/@comment-2601:187:8081:8EE3:E41A:B78D:1822:BC11-20190215202352/@comment-27219153-20190216101728

The number you are referring to is the data value. You can use a colon to specify a specific data value. If no colon is used, it will default to zero. This applies to vanilla blocks as well.

So for example if you want to set an area to orange wool, you can use //set 35:1 (If I recall correctly, 35 is the id of wool and 1 is the data value that corresponds to orange.)

Likewise, if you want to use ice Utumno bricks, you would use //set 510:2 assuming you have the default item ids where 510 corresponds to Utumno brick.