You have a strand of baroque cultured akoya (saltwater) pearls. They are baroque shaped because the nacre wasn't laid down evenly.
If you are interested in restringing them, we can help...there are stickied threads about restringing in the Lowly Beaders' Club forum. Restringing would enable you to remove any pearls that may be in bad condition (like the one in the center of the top photo) or at least to move them closer to the clasp where they would not be seen so much; it looks like a multistrand necklace and removing pearls could change the way it lies.