Final answer:
In the Dura painting, 'Samuel Anointing David,' David is depicted with a crown, which signifies his royalty and is the Imperial attribute in question.
Step-by-step explanation:
In the Dura painting, Samuel Anointing David, David is depicted with an Imperial attribute indicating his royalty. This attribute is a crown, which is a traditional symbol of royalty and power. It's worth noting that across different cultures and time periods, a variety of items have signified royal authority, such as scepters, thrones, and robes. For example, medieval kings could be depicted with crowns topped with fleur-de-lys, signifying their right to rule. In the context of depictions of royalty, other elements like the regalia worn by kings, such as kilts and royal beards, or artefacts like the Crown of Thorns acquired by King Saint Louis, are symbolic of their royal status and authority. Crown is a common symbol of kingship and sovereignty in art, often used to depict the royal status of individuals. If there's a specific detail in the Dura painting you're referring to, it would be advisable to consult the specific details of that artwork for accurate information about the depiction of David's royalty.