I've duplicated a gold ore vein for future use with a new ore, at the moment I haven't changed any property in the script problem is the duplicate is always depleted. I copied an ore vein from a mine in Tamriel and pasted it into my world and it was fine but duplicating in CK gives an empty vein. Why is this?

Check the original you cloned from.
If I am not mistaken, it needs a PickaxeMiningFloorMarker linked into it.
The player moves to this location when mining there.

I ran into a similar problem when making a custom new ore to mine.