For the proper attribution, I believe that you will have to measure size and wait of the coin and go through the steps described here:
https://docs.google.com/document/d/...8/edit?pli=1
and elsewhere in the comments here:
http://www.zeno.ru/showgallery.php?cat=11637
https://docs.google.com/document/d/...8/edit?pli=1
and elsewhere in the comments here:
http://www.zeno.ru/showgallery.php?cat=11637





















