Have a hammered sterling cuff necklace but its not marked. What is my option if any?

[sugarshall]

I have a lovely cuff coller necklace that I'm certain is sterling but it is not marked.  What are my options if any and you opinion of my quest.  

[inceptions]

You cannot list it as sterling (or even mention the word sterling in the listing) unless you KNOW it is sterling. Since there is no marking on it, it is more likely plated.