Triple-cherry jam

2 c Light sweet cherries
2 c Dark sweet cherries
2 c Tart red cherries
6 c Sugar
Juice of 1 lemon
Pit and measure cherries. Grind coarsely. Simmer about 5 minutes to soften skins. Add sugar and juice. Cook until thickened, 15-20 minutes, but no longer than 20 minutes. Skim and pour into hot sterilized jars. Adjust lids at once and process in boiling water bath, 212 degrees, for 5 minutes. Remove from canner and complete seals unless closures are self-sealing type.