What is the correct grade of Magic cards?
From TrollTraderCards:


  Near Mint / Mint:  ­Cards in NM-Mint condition show minimal to no wear
  from shuffling or general play
  
  Light Play: ­ Minor scuffing, drawing (including signatures or stamps)
  or slight bending. 
  
  Moderate Play: ­ May show any amount of wear, and any type of wear,
  but usually still legal for tournament play once sleeved
  
  Heavy Play: ­ As moderate play, although much more excessive. May not
  be legal for tournament use, even when sleeved.


But for a more in-depth I would use Star City Games's guide as it provides with you example images. You can find that here.

I would grade your card (without personally looking at it) between PL and HP using Star City Games's grading system, as I can't see if the card has much dirt in it but has that white spot near the top on the left. If it is just a blemish and the bottom and the card is also clean, then PL, if the card has some gunk in it overall, then HP.