That is alarming, G-John. You should see just ahead of the flats the proof marks from St. Etienne on the barrels themselves. On the flats should be a number of round punch marks which, as noted, are added to 10 to define the grade. You should also see the chamber length in either centimeters or millimeters and a nitro proof mark, usually PT. Key here is to look at the lever. It should have the word "Darne" in elaborate script in a small cartouche Between the ears near the breech when closed. If it does not, it is not a Darne but possibly a licensed copy from another maker.
Regards, Tim
