Prepare boiling water canner. Heat jars and lids in simmering water until ready for use. Do not boil. Set bands aside. Place pomegranate juice in a 6 or 8 quart saucepan. Gradually stir in pectin. Add up to 1/2 tsp. butter or margarine to reduce foaming, if desired. Bring mixture to a full rolling boil that can not be stirred down, over high heat, stirring constantly. Add entire measure of sugar, stirring to dissolve. Return mixture to a full rolling boil. Boil hard 1 minute, stirring constantly. Remove from heat. Skim foam if necessary. Ladle hot jam into hot jars leaving 1/4 inch headspace. Wipe rim. Center lid on jar. Apply band until fit is fingertip tight. Process in a boiling water canner for 10 minutes, adjusting for altitude. Remove jars and cool. Check lids for seal after 24 hours. Lid should not flex up and down when center is pressed.
*Quick Tip: To juice pomegranates, roll room-temperature fruit on a counter top, pressing it firmly to soften without breaking the skin. Holding the pomegranate over a fine sieve set over a bowl, use a sharp knife to cut out blossom end (crown), including the pith. Juice will begin to spurt out as soon as you puncture the skin. Using your hands, squeeze juice and seeds into sieve. Open the fruit and, using a small spoon, scrape remaining seeds into sieve. Use the back of a large spoon to press out any remaining juice from seeds. Measure 3-1/2 cups juice. Note: Wear rubber gloves to keep your hands from being stained. Makes about 6 (8 oz.) half pints.