This is a single 9ct gold stud with gold tone horseshoe charm and multi-colour crystals.
 
Horseshoes are symbol of good luck, which is said to reign from the eighth century, when Chaldeans thought its crescent shape represented various moon goddesses thus protecting against the curse of the evil eye. 
 
The multi-colours make this such a fun accessory that can stand alone, or be paired with another complementing earring, like the pearl and crown pictured above.
 
Measurements:
 
Drop approx 3.1cm
Width approx 1.6cm