Was about to post something about this.
Not free but
3 square+10/20g is fair for 1 pentagonal and same for 3 pentagonal+10/20g for 1 hexagonal
Here the problem
3 square+1 powder give 1 pentagonal which worth 1 powder which is a loss o nonsense transmute
3 pentagonal(worth 3 powder) +1 poder get 1 hexagonal this is non sense transmute too so you are spending 4 powder to make a gem that worth 4 powder
Replace that 1 powder requiriment for square and pentagonal transmute for 10/20g o either delete square and pentagonal transmutation from t