Sometimes I get asked to bless a rosary that I know will end up around the petitioner's neck. I don't have faculties to bless fashion accessories, but since it's a rosary I go ahead anyway. I have devised a special blessing for this occasion, and here it is:
May your blessing be upon all who find in this rosary a means to prayer and devotion.
May the prayers of the Blessed Virgin Mary preserve them from all danger of superstition.
We ask this through Christ our Lord.