A friend dropped off a bar of unknown alloy today. Tapping it on the concrete floor did not result in a satisfying "ring"...
However, it is marked- NL IND with four small hand stamps that read 16/12. The back side (flat) is stamped L 6102.
What did I get??

Sounds like a guessing game to me. Cast some bullets, and check the hardness. That should give you a pretty good idea.

Check melting/solidifying temperature too. That'll give you a clue to the alloy.

Thanx for that...
We`ll see after melting.