What noun describes the property of banknotes as a store of value and a medium of exchange rather than just a store of value?

Stocks, bonds, houses, and certificates of deposits (CDs) function as stores of value but not as mediums of exchange. It is not possible to steal houses, because houses are registered in people's names. In contrast, banknotes function both as a store of value and as a medium of exchange. It is possible to steal banknotes. If someone steals a $10 note from me, and I don't know who the thief is, I won't be able to recover the stolen $10 note.

What word describes this difference between banknotes and houses? I have seen this word before, but I cannot remember it. It is a noun (ending in -ity).

Solution 1:

Is liquidity the word you are looking for?
Lexico has

liquidity
NOUN

1 Finance
The availability of liquid assets to a market or company.

1.1 Liquid assets; cash.
a firm may be unable to pay unless it has spare liquidity

A banknote is classed as a liquid asset whereas my house is not. It is an asset, but has no liquidity.

Solution 2:

I suspect you might be looking for the word fungibility. Wikipedia describes it as

the property of a good or a commodity whose individual units are essentially interchangeable, and each of its parts is indistinguishable from another part.

That makes it correspond to banknotes of a given value, which a priori are all interchangeable, but excludes things like houses (and apparently bitcoin, because bitcoin identifiers tied to fraudulent transactions can be blocked [source (in French)]).