A potentially exempt transfer which would (apart from this section) have proved to be a chargeable transfer shall be an exempt transfer to the extent that the value transferred by it is attributable to property which has been or could be designated under section 31(1) below and which, during the period beginning with the date of the transfer and ending with the death of the transferor,—
has been disposed of by sale by private treaty to a body mentioned in Schedule 3 to this Act or has been disposed of to such a body otherwise than by sale, or
has been disposed of in pursuance of section 230 below or in the circumstances described in paragraph 1 of Schedule 14 to the Finance Act 2012 (gifts to the nation).