Looking for a fantasy book probably published before 1995, with a female protagonist, some form of princess I think. Early in the book she is caught in some sort of maze and manages to get out with some sort of dimensional (vorpal) sword? But the thing I definitely remember is that in the end she slays a dragon and collects the last drop of its heart’s blood as some sort of magical stone. Thanks!
The maze doesn’t match, but The Hero And The Crown has a princess heroine called Aerin who develops a fire-proof ointment and kills the last of the big dragons. (Small ones are more common) She gets the hearts-blood jewel. Later she climbs a magician’s tower (the big bad) and I think has some trouble getting out. She has a special sword called Gonturan which may help her. https://www.goodreads.com/book/show/77366.The_Hero_and_the_Crown
ha! Whoops. I’m glad you got the right title. The Blue Sword is the next one.
Could this be The Blue Sword, by Robin McKinley? Aerin definitely gets a stone that’s the last drop of blood from a great dragon’s heart.
Sounds kind of like The Hero and the Crown, by Robin McKinley.