add delimeter to list = [list, newItem]

Suppose I have a list that I am appending to like such:

list = [list, newItem newItem2]

How would I add a ; delimeter to each item so my list would look like this [1 2;3 4;4 5;] ??

[Walter Roberson]

Are these text items?

perhaps

list = [list; newItem newItem2];