MITRA Forum Question Details

I'm assuming this is your own work, still in the studio, and not a drawing by another artist that you've purchased. If that's the case, you could try gently reducing the crease with an agate burnisher or bone folder. Try first rubbing through thin paper instead of directly on the drawing, as the burnisher may emboss a shiny spot that will call even more attention to the crease. Test on a scrap of the same paper first so you'll know what the burnished passage will look like. Don't use any metal instruments, because they might leave an indelible mark.

A burnisher is really handy, by the way, for rough spots from excessive erasing and other corrections in commercial art. Probably not as many artists use them these days as when I was starting out. 

​No one but a trained paper conservator should attempt to reduce creases in works of art. That said, if the questioner is an artist, working on material of their creation, micro manipulation of the paper fibers might be tried, after extensive practice. Similar paper should be found and creased, to match, so extensive practice can take place on it, before anything is attempted on the drawing. The tool used to manipulate the fibers should be rounded enough to prevent cutting, but small enough that the pressure can be isolated to the crease. Stone implements are not sufficiently small and a chromed metal implement should be better. Practice on the practice sheet should then reveal techniques that can press fibers back closer to their original position, without undue pressure.
Hugh Phibbs