How sturdy would a slab of glass about 12 cm(for simplicity sake) thick be?

6 days ago

I already know compressed glass is able to withstand a massive load well over a tonne before cracking under the weight. I was wondering how much would crude raw glass be able to theoretically take. Also how much impact would it take to break through if anyone knows. This is for a story that is being written by a friend of mine and one of his characters is magically(yes i know this is a science place) making a glass wall out of sand in the desert to defend on an incoming attack. As mentioned already I know glass is deceptively resilient when not a simple pane, so in laymen terms, what would it take to get through such a wall?