Now with photos:
I acquired a small paper, string-tied package yesterday, was curious about it.
It is stamped in red “ECP 1?25 LOT 6 CARTOUCHES A BLANC MLE 1890-1900”
Being curious, I very carefully slid the string off and unfolded the paper. Inside were three smaller string-tied packages, each containing six cartridges with odd-looking paper bullets.
I only took one out to photograph, then carefully put it all back together the way it came apart. The headstamp is 2 ECP 24 BS.
Measuring the cartridge (along with Cartridges of The World) tells me they are 11mm French Ordnance Revolver loads. It also says that “Cartridges are scarce collectors items”.
I rather expect someone to come along and tell me that an importer recently discovered a warehouse full of these things in some dark corner of the world and they are basically worthless, but thought I’d see if anyone had any info anyhow.