old money

Old money refers to families who have been wealthy for at least three generations, as a term distinguishing them from the nouveau riche and parvenus (see template).Old money refers in the United Kingdom to the pre-decimal currency of pounds, shillings (or 'bob') and pence. It had abbreviation £sd. It also had guineas, crowns, sovereigns, (rare) gold sovereigns, halfpennies, and farthings. There were 240 pennies in one old pound, and 12 pennies in a shilling. See also: British coinage.Old Money can refer, informally, to any British imperial measurement (and sometimes to Fahrenheit temperatures).
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Noun
1. the inherited wealth of established upper-class families; "he was born with a silver spoon in his mouth"; "she is the daughter of old money from Massachusetts"
(synonym) silver spoon
(hypernym) inherited wealth

an inheritance, money that has been in the family for decades She bought that property with old money - money that her great-grandfather saved.