Cut the fruit in half crosswise and remove the seeds, half of the fruit also remove the skin. Then cut the prepared fruit into small pieces and place in a saucepan. If your calamondin tree has not produced a whole kilo of fruit, the missing amount can be filled with orange juice. Mix the sugar and Gelfix and mix well with the fruit. Bring the whole thing to a boil and simmer for 4 minutes while stirring. Finally, add a strong dash of Cointreau and pour the hot jam into twist-off glasses. Let cool standing on the lid. Makes about 4 - 5 glasses.