Difficult to determine anything conclusive with the blurry photo provided but I wouldnt rule out that this example was once turned into a piece of jewelry and what you are seeing is part of that puzzle. I see 2 rather fuzzy metallic blobs near the Eagles Breast and a few defects near the rim.
Edit. Please provide photos of both sides and the rim if possible. Look for hints around the rim if it was once mounted in a bezel for instance.