Master Brushed Cobalt or Melted Pontils?

[MrClean]

I have never posted for help with ID'ing a marble before, however I HAVE read hundreds of other people's posts! This group has helped immensely in my quest to ID roughly 12,000 of my late-father's marbles I inherited last year.

This marble is nearly an inch in diameter (0.98 in) and doesn't seem to fit the pics and descriptions I've seen for a Master Brushed Cobalt. The color is definitely cobalt-y. The white coloring is definitely coated on the exterior of the marble (as evidenced by the chips), but is also internal. As you go around it almost seems to move from interior to exterior. 

The white has a chalky texture and appearance in places. I can't identify any obvious cut lines. I've handled and examined hundreds of Germans but this doesn't appear to have ground pontils. I've never knowingly seen a melted pontil before. 

What do I have here? Thanks in advance!