Nail (relic)
Relics that are claimed to be the Holy Nails with which Christ was crucified are objects of veneration among some Christians. The question has long been debated whether Christ was crucified with three or four nails, and can hardly be answered with references to medieval treatises or ancient iconic traditions. The details can be followed, however in the Catholic Encyclopedia (see external link below). The belief that three nails were used is called Triclavianism.
One of the nails is said to have come to rest in the Iron Crown of Lombardy.
The Catholic Encyclopedia remarked that "Very little reliance can be placed upon the authenticity of the thirty or more holy nails which are still venerated, or which have been venerated until recent times, in such treasuries as that of Santa Croce in Rome, or those of Venice, Aachen, the Escurial, Nuremberg, Prague, etc. Probably the majority began by professing to be facsimiles which had touched or contained filings from some other nail whose claim was more ancient. Without conscious fraud on the part of anyone, it is very easy for imitations in this way to come in a very brief space of time to be reputed originals. The bridle of Constantine, for instance, is believed to be identical with a relic of this form which for several centuries has been preserved at Carpentras, but there is another claimant of the same kind at Milan. Similarly the diadem of Constantine is asserted to be at Monza, and it has long been known as "the iron crown of Lombardy."
