What is the quality or state of being inconvertible; not capable of being exchanged for, or converted into, something else; as, the inconvertibility of an irredeemable currency, or of lead, into gold called?

inconvertibility — The quality or state of being inconvertible; not capable of being exchanged for, or converted into, something else; as, the inconvertibility of an irredeemable currency, or of lead, into gold. (Webster's 1913.)

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