Wash and hull strawberries. Combine strawberries and sugar in a large Dutch oven; stir gently to avoid bruising berries; let stand 3 to 4 hours.
Slowly bring strawberry mixture to a boil, stirring occasionally until sugar dissolves. Stir in lemon juice. Boil 12 minutes or until berries are clear, stirring occasionally. Remove from heat, and skim off foam with a metal spoon.
Carefully remove fruit from syrup with a slotted spoon, and place in a shallow pan. Bring syrup to a boil; cook about 10 minutes or until syrup has thickened to desired consistency. Pour syrup over fruit. Let stand, uncovered, 12 to 24 hours in a cool place. Shake pan occasionally (do not stir) to allow berries to absorb syrup and remain plump and whole. Skim off foam.
Ladle preserves into hot sterilized jars, leaving 1/4-inch headspace; cover at once with metal lids, and screw bands tight. Process in boiling-water bath 20 minutes.