These "miss-matched" earrings use an 0.5" long 3D silver-plated lock charm while the other is an 0.5" long 3D silver-plated key hanging from an 0.75" long length of silver curb chain.  The earrings use stainless steel leverback earwires and are 1.5" long.  
 
All metal used is hypoallergenic, nickel-free, and is sterling silver, silver or gold-plated, or stainless steel unless noted otherwise. Every item is handcrafted, custom-made, nothing mass-produced.