Prepare the Kumquats

Cup of Yum
1. Wash the kumquats well, dry and then deseed and slice the fruit lengthwise, using a sharp knife so the rind is in long strips.
2. Place into a large pot.

Add the Water and Measure the Mixture

1. Pour the water into the sliced kumquats in the large pot. Add the juice of the orange and stir well.
2. Measure the amount of the mixture by ladling into a large measuring cup and pouring into another pot or bowl. Ours measured 10 cups (or 2.35 l ).
3. Add the mixture back into the large pot, bring to a boil, and simmer for about three to five minutes or until the rind is soft. 
4. Remove from heat and add the same amount of sugar as you measured in liquid. We measured 80 liquid ounces, so we added about 5 lbs of sugar (2.25 g). (We usually add a little less than a 1:1 ratio, so if you want to do the same, please do so, like 4.5 lbs.)

Cook the Kumquats

1. Put the pot back onto the burner over medium high heat and bring to a boil, stirring frequently with a wooden spoon.
2. If you see any seeds, pull them out and discard.
3. Bring the marmalade to a rolling boil and it will begin to look like this. You can remove the scum as it settles along the side. 
4. It will eventually end up looking like this after about an hour of boiling. You can check to see if it's reached the setting point by placing a saucer in the freezer then dripping some of the hot liquid on it. If you run your finger against it and it wrinkles, it's ready. You can also use a candy thermometer and take it off the heat when it reaches 220℉ (104℃).

Fill the Jars

1. Have the sterilized jars ready near the stove (washed, rinsed with boiling water, including the lids) so that they are still hot. Ladle the jam into the funnel to fill the jars. Don't hold the jar while filling.
2. Be sure the jar is on a counter or table before filling with hot kumquat marmalade.

Clean and Seal the Jars

1. As soon as you fill each jar, clean the rim with a damp cloth and close the lid immediately. Repeat until all the marmalade has been filled into the jars.
2. You can process the jars in a water bath according to your favorite canning method, or you can just keep the jars in the fridge instead. Most times, the jar lids will seal on their own, but this isn't an approved method of jam-making in the US.