Grate the zest of 3 of the oranges and cut into fine matchsticks. Place the zest in a small saucepan with 1/2 cup of water and bring to a boil. Reduce heat and simmer for 10 minutes. Juice the remaining oranges and put the juice, any of the pulp and seeds from juicing, the lemon juice, and 4 1/2 cups of the sugar in a preserving pan and simmer for 30 minutes over low heat. Drain the grated zest and stir it into the juice mixture. Mix together the pectin and remaining sugar and stir mixture into the saucepan. Cook for 10 minutes. Let mixture cool slightly, pour the marmalade into sterilized jars and seal.
