white rent
now historical
noun
= quit-rent; specifically (in Devon and Cornwall) a rent or duty of eight pence a year payable by every tin miner to the Duke of Cornwall.
- The association with silver money found in some of the quotation evidence and in N.E.D. is likely to reflect folk etymology..
Origin
Mid 16th century; earliest use found in All Statutes Stannary. Probably a variant of quit-rent, with reanalysis of the first element as white.