[mmooss]

> It could sooner be replaced by a colon than a full stop.

Use it as you like, of course, but by the rules of grammar that is quite misleading. A semicolon must separate (or connect) two independent clauses, just like a period; a colon has many uses. Here is the Chicago Manual of Style:

"A colon introduces an element or a series of elements illustrating or amplifying what has preceded the colon. Between inde­pendent clauses it functions much like a semicolon (see 6.56), and in some cases either mark may work as well as the other; use a colon spar­ingly, however, and only to emphasize that the second clause illustrates or amplifies the first. (The colon usually conveys or reinforces the sense of "as follows"; see also 6.64.) The colon may sometimes be used instead of a period to introduce a series of related sentences (as in the third ex­ample below)."