question about adding sockets

[Kapone]

If I add sockets to an item through Larzuk, it just adds one socket. Can I add another socket to the SAME item in another difficulty setting as a quest reward, or can you only add one socket to each item this way?

For instance, my HoZ has 1 socket now, and I haven't socketed anything in it yet. Could I do it to this?

Also, my shako, for example, I added a socket to through Larzuk, and put a ptopaz in it for higher MF. Could I add another socket to this item too (if it works in the first place) considering I've already placed something in it?

Thanks in advance.

[purplelocust]

The Larzuk socket quest adds sockets depending upon the item type and can't be used on items that are already socketed. For a unique, like your HoA, there can be only one socket. A plain white item or unsocketed ethereal (grey) will get the maximum number of sockets for it's item type and ilvl. A rare will get one socket and a magic item will get either one or two, if two is a possibility based upon item type.

[Anthraquinone]

simply: you cannot socket an item that already has socket(s)