Bowl Rim Residue After Cleaning

Hi folks,
I just bought my first estate pipe off ebay to try my hand at some light restoration. I got this Guido del Vecchio for a song. Not sure what shape you'd call this... not quite an oom paul, is it? Bent billiard? It's quite big, and has a beautiful butterscotch acryllic stem.




I am pretty stoked. So I'll go out tomorrow and get a reamer and some other supplies at the tobacconist. But tonight I thought Id get to work cleaning the stem with an isopryl alcohol-soaked pipe cleaner. So far, so good. Then I decided to remove the gunk off the bowl's rim:


I started off using spit and a rag, but it didn't seem to make much difference, so I moved to an old toothbrush, and finally the alcohol and the rag. I've only just now read that rubbing alcohol should never get near the briar. Oops. So now there appears to be some yellowish-white residue in the grooves of the rusticated finish. 8O


Any ideas what this is, and how to fix it? Thanks in advance, friends.

thanks for the reassurance, friends. I'll be sure to do a salt/alcohol treatment. This bowl tastes like someone sprayed lysol into it! :X