Pit and halve your unpeeled apricots. Puree them in a food processor or other appliances with similar capabilities. You don’t need to make it smooth, but try to make the big chunks smaller.
Measure out exactly 5 cups of prepared fruit into a large measuring bowl.
Do the same process for the cherries. Wash them, halve them, remove the pit and puree them. For 1 cup of puree you’ll need about 2-2 ½ cups of fruit. Puree the cherries more than you did the apricots, try to get them the texture of baby food.
Turn the heat to medium high and put a lid on it.
Allow the mixture to heat up for about 10 minutes, stirring once every 2-3 minutes. At this point, the jam looks more orange than red, but the color changes as it cooks.
Mix ¼ cup of sugar and the pectin in a small bowl. Add to the fruit n the stockpot. Add in the butter to reduce the foaming and bring the mixture to a full rolling boil on high heat.
Stir in the remaining 4 ½ cups of sugar. Return to a full rolling boil and let it boil for 5-10 minutes.
After about 5 minutes, put a spoonful of jam into a little bowl and place t in the freezer. After a minute or two that jam sample will be cooled and you can see if your jam will set up. If it colls and is runny, add ¼ cup sugar to the pot and boil for an additional 5 minutes, stirring constantly. If the sample sets into a nice jam texture, it’s done.
Remove the pot from the heat. Skim off any foam with a metal spoon if desired, or stir it into the mixture.
Ladle immediately into prepared jars filling to within ⅛ inch tops. The jars will be almost entirely full with only a small amount of headspace remaining. Wipe the jars rims and threads, and cover with the 2 piece lids. Immediately turn the entire jar upside down and do this with all of the remaining jars.
Let the jam sit untouched for 24 hours. Then turn it back to its right-side-up position and press the center of the lid. If it springs back up like a button, you’ll need to place that jar in the fridge because the seal didn’t hold, eat it soon. If the lid doesn't bounce and there is no movement, then it’s sealed and you can place it in the pantry for 6-8 months. Make sure to label the jars before storing!
