Some questions about a William iii 6 pence

Hi, I recently got this William iii 6 pence, but there have some little hole on it's surface, I wonder that what causes these little holes? And if I send  this coin to ngc or pcgs,  will it get xf or au rating?

I saw an article or something once about shipwreck coins or coins found in the sea, the long exposure to salt water produced little pits on the surface. This could be one explanation, or maybe just being banged about in a bag full of small caltrops! 
 

As for Grade I think XF is the highest you would get, and more likely even below that. 

Old planchets never were perfectly smooth. Looks normal to me, no salter water leaching or cast pitting.

King

I saw an article or something once about shipwreck coins or coins found in the sea, the long exposure to salt water produced little pits on the surface. This could be one explanation, or maybe just being banged about in a bag full of small caltrops! 
 

As for Grade I think XF is the highest you would get, and more likely even below that. 

Got it, thanks for your answering

Idolenz

Old planchets never were perfectly smooth. Looks normal to me, no salter water leaching or cast pitting.

Yeah, i have a Charles II crown with saltwater damage, it is indeed quite different from this one