maNi

[Rolf Heinrich Koch]

Dear Members,
in Prakrit literatur the term poyaya (mentioned together with mAna = measure 
and therefor to explain as weight < Skt. pautava) is combined with maNi-Adi as 
bahuvrihi. In other words the term poyaya is characterized with maNi etc. 
Does someone know the relation between maNi (pearls) and weights?
Moreover I need examples about wares which got weighed by use of a boat (pota) 
in the water.
Thanks Heiner