Here's an example of the new CC public domain mark (for the Mona Lisa):
<p
xmlns:dct="http://purl.org/dc/terms/">
<a rel="license"
href="http://creativecommons.org/publicdomain/mark/1.0/">
<img
src="http://i.creativecommons.org/p/mark/1.0/88x31.png"
style="border-style: none;" alt="Public Domain Mark" />
</a><br />
This work (<span property="dct:title">Mona Lisa</span>, by <span
resource="[_:creator]" rel="dct:creator"><span
property="dct:title">Leonardo da Vinci</span></span>), identified
by
<span resource="[_:publisher]" rel="dct:publisher"><span
property="dct:title">Ryan Kaldari</span></span>, is free of known
copyright restrictions.
</p>
I imagine we can put whatever icon image we want in the mark. The
metadata is the important stuff (for search engines). Anyone want to run
with this on Commons?
Ryan Kaldari