For the nectarine-white currant jam, cut the nectarines into very small pieces. Strip the currant from the stems, add to the nectarines and mix with the preserving sugar. Leave to marinate for a few hours.
Bring fruit pulp to a boil and boil for 6 minutes until bubbly, stir in liqueur. Fill nectarine-white currant jam into sterile jars and seal immediately.