1876 Seated Liberty Half Dollar/Foreign Objects & Die Stamps

Hi. I'm really new at this. Found an old Seated Liberty half dollar in storage. At first it looked like it was run over by front-end loader. It has three shallow depressions on obverse (lengths: 1/4", 1/2", and 7/8"). On the reverse, a faint impression appears to follow the long one.
On the obverse the two small ones are less than 1/8" wide, and the longer one is almost 1/4 " wide. Within each of the small ones there is a STAR, and within the long on I can make out several of the horizontal bars of the Shield and folds of dress (as if heated and smeared). All three depressions start at rim at (L)10:00, (M)11:00, and (S)12:00 and slant to their opposite counterparts.
If you drew a line at a right angle to base of coin from outside right edge of Liberty's head, it passes the last number in date about an 1/8" to the right of it.
I've searched and read many articles, but can't find anything about pieces of broken dies/coins getting between die stamp and blanks. Any help is appreciated.