Tombstones aren’t too unusual as a source, but sometimes they aren’t highly accurate. And often they only give names and birth and death years. But sometimes they have additional information that can be useful and point your research in the right direction. I’ll post some examples from my own family below.
Sometimes stones list military service, branches, and/or units.
Sometimes, stones will list the parents of the deceased. This is especially helpful if you have a lot of people in your tree with the same name.
This is my aunt and her husband. Sometimes, if you’re lucky, stones will have full dates and even marriage dates (kind of tiny above their last name it says “Together Forever. Married 7-4-1960).
This is my great-great grandfather. His stone tells the city and country of his birth. And it’s actually correct, although his birth name was Johan Axel Rustad.