2 c. cranberry juice
2 c. grape juice
7 c. sugar
1 pouch Certo fruit pectin

Pour sugar and juice in large heavy saucepan. Stir gently and heat slowly to a full rolling boil 3 to 4 minutes. Remove from heat, stir in Certo at once. Bring back to full boil 2 to 3 minutes. Skim off any foam with large metal spoon. Immediately ladle into hot jars, leaving 1/8" space at top. Quickly seal jars by covering with hot canning lids, and screw on bands.