Beaker deleted?

Windows are made of basic glass you can make out of pretty much any sand; This kind of glass however is very vulnerable to thermal shock... That is to say, If you heat it rapidly, or over direct fire heat, it will shatter.

Chemistry beakers are made of a very specific blend of silica, boric oxide, and s a few other things that results in borosilicate glass- This kind of glass is very stable under rapid or active heating, Which is why we use it in chemistry situations; It doesn't shatter over fire the way typical window glass would.