What is the ruling on placing markers on graves?

Question:
May Allah reward you, Honorable Shaykh. This questioner says: I saw in some graveyards that there are markers on the graves made of paint, stones, wood, and other things. Is that permissible? I ask for clarification on this issue.

Answer:
Placing a marker by which a visitor to the grave can identify the grave of its owner, such as a stone or something similar, is permissible. Placing a stone or placing a stick driven into the side of the grave is permissible. As for colors, painting with paint, plaster, or other colors, this is forbidden. This is because the Prophet (peace and blessings be upon him) forbade plastering graves. Paint is a type of, well, it is close to plaster because it remains, because it is a color that remains. And if you do this, others will do it, and then the entire graveyard becomes full of colors from paints. This is forbidden. It is not permissible to paint with plaster, it is not permissible with paint, and it is not permissible. Likewise, writing on the grave is forbidden. It is forbidden to write the name of its owner on it, or to write a number, letter, or symbol on it, because the Prophet (peace and blessings be upon him) forbade writing on graves.
In all their types, and dyes in all their types, they are not permissible on graves. As for placing a marker that only you know, a stone, an iron bar, or a stick driven beside the grave that only you know, that is permissible. Yes.