Krause has the value listed as "-" for the date and mintmark. It is the only 1780W certified at PCGS or NGC. Further complicating the issue is the wonderful star that has been scratched on the cheek. http://www.pcgs.com/cert/83734087 Edited to add...I am not expecting a specific number value (unless you want to figure one out) but more of a "factor consideration/thought process." For example, "I would compare it to "x" and add a little more for rarity, but take some off for the graffiti, thereby reaching a consensus of "y."
Therein lies some of the rub, so to speak. What is the value of a problem free example? Krause does not list a price and I can't find any available for sale or any past auction sales for comparison.
Where have you looked ? Between these 3 websites you can usually find most coins. https://coins.ha.com/ http://www.coinarchives.com/ https://www.acsearch.info/
Thank you for the websites. I bookmarked the last 2 for future reference. I had checked Heritage, but the other two sites are terrific...but no 1780W Ecu. Thank you for the Gadoury reference. That seems to be the best starting point I have right now. I have a Gadoury that goes from 1789-2015, so I am assuming there is another reference that covers pre-1789.
Hmmm, once I had time to look I found 3 of them at just 1 site. https://www.acsearch.info/search.html?id=1889798 https://www.acsearch.info/search.html?id=1223924 https://www.acsearch.info/search.html?id=1391293 Just a hint, when searching, any of them, don't make your search terms too specific, keep your search terms broad. You'll have far better luck that way. I only check the one site, but the only search terms I used were - 1780 ecu.
I think you need to treat it more like a type coin rather than worry about the specific date/mint mark combination. Find sales of similar coins then subtract 40-50% for the graffiti. I doubt there are many collectors looking for those by date and mint mark and if there are, I really doubt they'd be interested in a damaged example.
That would probably work or at least get you a close idea as long as you searched out coins with a similar mintage. About 10% of the type had a mintage under 10,000. So you should be able to find some of them.
I think I will put some rare counterstamp right on the cheek, thereby covering the star and adding value at the same time. Just kidding. I do wonder if there is a way to fix that star. It will go from "VF-details graffiti" to "VF-details repaired." I don't see much difference in that and the eye appeal would improve.
This one does not have the extra star. http://www.cgb.fr/louis-xvi-ecu-dit-aux-branches-dolivier-1780-lille,v39_0311,a.html Christian
The star graffito, while unfortunately detrimental to the coin's value, is interesting. I find myself tempted to imagine someone of Royalist sympathies adding it to poor Louis' face sometime after his date with the guillotine; sort of as a superstitious gesture- a posthumous blessing, perhaps- in other words, the opposite of a "damnatio memoriae". Of course that's entirely speculative, and there's no way to tell. I have seen damnatios on French and other coins- scratches and deep cuts on the necks of kings who were beheaded in real life. Napoleon III (though not beheaded) seems to have gotten quite a bit of numismatic satire after he lost the Battle of Sedan to the Prussians in 1870. But what the original meaning of that star is on this Louis XVI coin is, who knows. Could be somebody was just bored and felt like scratching a star into the coin. But it's fun to think about, and I'd rather have a coin with interesting graffiti like than than some plain old scratches. Damaged or not, it's a neat piece.