Solomonic Bullets are bullets made from melted down Silver Denarius Coins recovered from beneath the temple mound in Jerusalem. There are a finite number of them in existence, currently only 15 remain.
The bullets are engraved with powerful magical symbols and are used to disrupt Thaumaturgy or to cause irritation and harassment to creatures of the unknown.
In 1936, Father Martin Ambrose Fletcher used 5 such bullets to drive off the Black Court Vampire, Emeric Dane during an attack on Saint Peters Basilica. Although they could not kill the vampire, they caused him extreme agony and he withdrew from the fight.
The bullets are currently .38 caliber revolver rounds and are fired from a stub nose .38 Colt police special revolver owned by Father Fletcher.
There is reason to believe that Father Fletcher has additional coins which could be converted into bullets, although this is unclear.