Berry Preserves - cooking recipe

Ingredients

2 lbs berries (blackberries, raspberries, loganberries, etc.)
4 cups sugar
1/4 cup lemon juice (optional)

Preparation

Combine berries and sugar; let stand until juices begin to flow, about 10 minutes.
Bring slowly to a boil, stirring until sugar dissolves.
Add lemon juice, if using.
Cook rapidly almost to gelling point.
As mixture thickens, stir frequently to prevent sticking.
Remove from heat.
Skim foam if necessary.
Ladle hot preserves into hot jars, leaving 1/4 inch head space.
Adjust two-piece caps.
Process 15 minutes in a boiling water canner.
Yield: about 4 half pints.