Vintage 9ct Gold "21" Key Charm

There are many designs of a "21" key, but there is something about this one that we really like. It's solid, which means it's not going to dent or bend easily, and it feels great hanging from a chain or a charm bracelet. It's simple but beautiful. 
 
Condition: Excellent vintage condition. There is no jump ring, but the top of the ring can easily be hung from a chain.
 
Hallmarks: 9 375 for 9ct gold. The rest of the hallmarks are indistinguishable, but we know it dates to pre-1975 due to the gold hallmark.
 
Weight: 1.25g