The cistern chain is a series of linked cups that worked on a gear to bring water up from the cistern.  The cups can be separated and used individually or in series.  I have seen them planted and, if each were drilled, could be put to work as a rain chain. 

The chain is made of galvanized steel which has corroded - this is not a new item.   The price below is per cup.  Each cup comes with a plastic liner should you wish to use it as displayed in the third image - a vase!