The Times of Israel tells us more about a ring discovered from ancient times that most likely fell off during a ritual bath:
Some 2,000 years ago, a Jewish penitent misplaced a bronze ring during his climb of a 600-meter-long (about 2,000 feet) pilgrims’ thoroughfare leading to the Temple Mount. While the recently recovered ring is today heavily corroded, its central blue semi-precious stone still sparkles.
The ring was recently discovered at the City of David’s Sifting Project in Emek HaTsurim, in a bucket of dirt excavated from a structure on the side of the broad 7.5-meter (24-feet) -wide road that is thought to have housed a ritual bath, or mikveh. According to City of David archaeologists, the worshiper likely lost the ring when fresh from ritual purification prior to his ascent to the Temple Mount.