Modernist Pottery Bowl, Overpainted?

I am not quite sure but to me it looks like the black finish is later addition. Should I strip it?
The piece looks like some Japanese bowls I've seen but they usually are not so freeform.

 

The black is part of the glaze but the firing may not have been the right temperature or it just dings easily. I've never seen anything like this before but it may just be student work.

 

Seems like there is another type of glaze under the black, more visible on the interior bottom. That is why I thought the black was not the original finish.

 

Yes I see that. It's just 2 different types of glazes slathered on. A pottery maker would know the names / types. The black just looks like a flat black matte glaze to me, while the white is a bubbly one. Then the piece got a ding in the top of the black.

Some dealers could try to paint this ding to hide it but most pottery collectors would prefer to see the ding and to repair it (or not) themselves.

 

It turned to be just painted. Have not finished completely with the cleaning but I like the original glaze better.

 

It'll probably sell better without the ding.