Stamp In Silver Metal And Exotic Nuts, Circa 1900

Silver metal stamp and seed called "Hamburger Bean", Mucuna Sloanei.
The stamp itself attached to the seed by a foliage motif is square (1.13 cm x 1.13 cm) and presents the letters C and E
Probably French work
Period around 1900
Good general condition

NB: This seed comes from Robust and climbing lianas, distributed throughout the American tropical world, in Africa and in the Indian Ocean. This species of Mucuna, used for a very long time in many Native American, American and Indian medicines, contains an amino acid precursor of dopamine that current medicine uses to treat Parkinson's disease.
The seeds of these lianas have a very hard and waterproof integument which allows them to float and drift without damage in the ocean currents.

NB: This stamp could have belonged to a scientist, a botanist, a doctor or an adventurer...

PS: I thank my colleague and friend Antoine Claeys for his valuable help in finding this information.