Are they lucky? You need to decide for yourself.
In many cultures over the centuries people have thought of them as a good luck charm, ward off the evil eye, or the shape being like a crescent moon was a symbol of fertility.
Personally I love them.
Different types are given on 18th or 21st birthdays or wedding gifts.
These made from Iron, you can choose a standard horseshoe
or one with hooks. You decide.