The "right click the icon" handles the MAP but the markers with your stuff are still there. ignore them or, if it really bothers, you;

1. Use the pickax to dig a deep hole next to it (not TOO close, miss the marker).
2. With a FULL inventory open the marker (prevents you taking anything).
3. While FACING the hole drag each item out and throw it in the hole.
4. When last item leaves marker blows up (usually).
5. After a while you'll find the hole is empty.