Celtic Collection is a Collection of Charms, that are a collection of knots which are as old as the 5th century. They are used in Pagen and Christian religions.
Included in these Charms is the Shamrock, which is supposed to ward of evil as well as used as a Symbol of the Holy Trinity.
Celtic Knots have no beginning or end and are used to ward off evil and to protect the wearer. They also are used as a sign of love and devotion and eternal love.
There are some, which also are linked with the three elements, Water, Earth & Fire.