Fritz Hansen Mid-Century Modern Wire Chair

A friend of mine has 2 of these chairs and I told her I would find out more about them.   She doesn't know where they are from or what was paid for them.  She would like to know what type of chairs these are and how much she can get if she sells them.

From my internet research they look like mid-century modern wire chairs attributed to Verner Panton by Fritz Hansen.  The only thing is, what I found online is chrome.  My friend's chairs are white.