White dirt in jatoba fretboard

Question

My brand new JemJR has weird white dust inside wood. I already tried to clean it using some paper and water. It looked perfect right after cleaning it, but it returned once the fretboard was dry.

What is it? How could I remove it?

Answer 1

This was answered on the Woodworking stack: getting slurry out of wood grains

It's liquified sanding dust. Fine-grit paper creates tiny particles which mixed with the finish and dried into the grain.