French rarity scale: A question

[Levantiner]

I have a French language coin book ( Corpus Luiginorum)   in the book coins are given a rarity rating ( C, NC, R1- R5)   I have looked all through the book and no where do I find a table defining what each rarity rating means. I am guessing that R5, the highest rating I have seen in the book, equates to R7 ( meaning 1-2 known coins) but of course  that is just a calculated guess on my part.  Can any one enlighten me as to whether there is a standard French rarity scale?

[chrisild]

Cannot really help you with that, but it seems that the same rating system is also used among collectors of ancients. See this (Excel) document: http://www.forumancientcoins.com/dane/claudius2.xls

From the "Notes" tab:
Rarity ratings   
C: common, seen in a majority of the collections that the RIC authors reviewed
S: scarce, in larger collections
R: rare, very seldom seen. R5 = one only known, R4 = only a handful known… rarity progessively decreasing to R

(RIC is short for Roman Imperial Coinage; will not matter much here. )

Christian

[Levantiner]

Thanks The book is numismatic  ( as opposed to Collector) oriented,  it seems to have a strong technical/academic focus  so I think  the ancient rarity scale is probably the most likely.   

PS(A joke) I don't think we should tell American grading companies about the Rarity scale issue. Could you imagine the out come MS64  R4.567  it would make slabbing even more incomprehensible!!!!