In predecimal coinagecurrency notation in the UK, the symbol should be the solidus symbol, because the word "solidus" comes from the Latin name of a coin. Pounds shillings and pence were also denoted with £, s, and d, which came from the Roman silver coinage denominations librae, solidi (plural of solidus), and denarii (plural of denarius).
The solidus wasn't used as a divider. It actually stands for shillings/solidi
So you would never write £1/5/- It would be written as £1 5/-
Pennies were added after the solidus, for example £1 5/9d, sometimes with or without the d.
It could also be written as £1-5s-9d, sometimes with a centre dot as separators instead of a hyphen, or a long dash instead of a hyphen. Sometimes just a space separated pounds from shillings. For example £1 5/-
It's also interesting to note that instead of £1 5/- people would often convert it to shillings when writing it - for example 25/- or 25s.
My sources: An old person (82) who I just asked. Also if you look at some old newspaper adverts you will see how they actually did it. Sometimes the solidus was something more akin to a long apostrophe. There's an example here.
Another example here for a higher priced item priced in shillings. In this case 79/-6, instead of £3 19/-6d.
Another interesting thing to note is that very high priced items such as a television set were often priced in guineas - abbreviated GNS. A guinea was £1 1/-. So in this example 78GNS would be equivalent to £78 and 78 shillings, or £81 18/-
All I can say is thank God for decimalisation. Imagine having to work this all out in your head! 240 pennies to the pound, 12 pennies to the shilling, 20 shillings to the pound, 21 shillings to the guinea. There were also halfpennies to contend with, ½d, and prior to 1961 farthings, ¼d. It was completely insane!