I'm having black stools while taking iron tablets and folic acid is that normal please?

Yes: Taking Iron supplements can result in stool changing to a dark color. This is normal. You may notice that you are becoming constipated. If so try using a stool softener.

Normal: As the iron supplement is the culprit here. If you are having bright red in your stool or blood clots or the stool has a "tar-like" texture then something else may be going on.