A sweet patient just sent this in to share:

small batch of unsweetened Blueberry Jam

The following amounts make a small batch of 2 medium sized jars, double up ingredients as needed.

The jam will last about three weeks after opening.

Ingredients:

4 cups of mashed blueberries

1 packet of pomona universal pectin

4 tsp of calcium water (made from calcium in Pomona pectin box) 

Mash the blueberries in a deep pot with a potato masher until pulpy or with a hand blender for a smoother jam, then measure 4 cups into a large saucepan.

Heat the blueberries over medium heat until they become a rich, deep purple color, stirring for about 10 mins, add the 4 tsp of calcium water and stir well. 

Bring to the boil, add the whole packet of pectin, stirring it in well, boil for 5 mins.

Remove from heat.

Pour into sterilized glass Jam jars, then process these in a pot of boiling water for 15 minutes, then refrigerate or freeze. lasts a couple of weeks once opened.