Directions Rinse the calamondins and cut them in half crosswise. Put the oranges in a heavy non-corrosive saucepan and add the water. The next day, return the orange/water mixture to the stove and bring to a boil. Remove the pot from the heat, ladle the marmalade into jars, and seal.
In a large, heavy pan combine the calamondin juice, sliced rinds, water and sugar. Heat until the sugar is dissolved and bring to a boil, stirring occasionally. Reduce the heat to medium and continue to cook the mixture for 15 minutes. Add the butter a little at time to help reduce the foaming and scum that can develop.
Cut the Calamondin oranges in half and remove the seeds (I do this on a plate, so I don't waste the juice) Put the oranges with the peel, in a food processor.
Place a calamondin rind on a cutting board and flatten it out. Use a very sharp knife and slice the skins very thinly. Repeat this until you have about 3/4 cup of calamondin strips. In a large, heavy pan combine the calamondin juice, sliced rinds, water and sugar. Heat until the sugar is dissolved and bring to a boil, stirring occasionally.