Yeild: about 6 half-pints
4 1/2 cups blueberries
1 package (1.75oz) powdered pectin
5 cups of sugar
1 tablespoon grated lime peel
1/3 cup lime juice
Crush blueberries one layer at a time. Combine crushed blueberries and powdered pectin in a large sauce-pot. Bring to a boil, stirring frequently. Add sugar, stirring until dissolved. Stir in grated lime peel and lime juice. Return to a rolling boil. Boil hard one minute, stirring constantly. Remove from heat. Skim foam if necessary. Ladle hot jam into hot jars leaving 1/4" headspace. Adjust two-piece caps. Process 15 minutes in a boiling-water canner.
Source: Ball Blue Book of preserving