Peel.and pit nectarines.
Coarsely chop both fruits.
Place chopped fruit in a large sauce pot.
Stir in lemon juice and pectin.
Place over high heat and bring to a rolling boil, stirring occasionally.
Add sugar and return to a rolling boil.
Boil hard 1 minute, stirring constantly.
Pour hot into hot jars, leaving 1/4-inch head space.
Process 10 minutes in boiling water bath.