KM-364 variety, Struck at the Lisbon mint.
Now this is the kind of coin we always enjoy listing.
While this is an obtainable issue in middling to average unc., this example is off the charts (actually, it takes the chart and chucks it out a window).
A superb, original, 185 year-old über-gem with razor sharp details, stunning cartwheel luster, all but perfect surfaces, lovely golden color and delicate pull-away toning above the letters in the legends and a coin which, to the best of our knowledge, could not be improved upon for any amount of money.
This coin is from the CRO archives and is not currently available for sale.