Mysterious bracelet marked JM?

by Marie Jansson
(Sweden)

Hello!
I just bought this bracelet, (for 25 swedish crowns,(2.5 euro) and wonder about age and the mark "JM" in a box, and also a mark that looks like four mountains in front of each other with a moon (sun?) above to the right...Any idea what this means? I love this bracelet, and hope the 4-leaf clover pattern bring me some luck..
Hoping for answer.
Thankyou
Marie in Stockholm, Sweden