Are those pics all of the same piece? I'm no expert but it looks like a piece of a fish or a bird effigy? Is it rock or bone...I assume rock? REALLY cool.
Those lines resemble tally marks, so they might not necessarily be sharpening grooves. For what it's worth, and I'm not sure anyone knows the reason, though there must be theories, broken artifacts were often decorated with tally marks. I've seen articles on the subject and will post a link should I find any. This was apparently often the case with broken gorgets and other decorative objects....
Edit: tally marks are very common on pendants and gorgets in any case, so I'm not sure how you would know for certain if they were so placed after damage to a piece. Such decorative objects were frequently decorated with what collectors have come to call tally marks. And so a series of dashes on the edges of a pendant would generally be interpreted as tally marks rather then sharpening grooves.