Peel peaches and roughly chop them. Toss them with 1 1/2 cups of granulated sugar and let the peaches macerate at least two hours and up to 72 hours.

When you're ready to cook, combine the fruit and their juices with 1 tablespoon calcium water in a low, wide pan. Bring to a boil and cook until the fruit is tender and the syrup thickens. Add cinnamon, nutmeg, and lemon zest and juice.

Whisk the pectin into the remaining sugar and stir into the softened fruit. Cook for another 3 to 4 minutes, until the jam starts to thicken.

Funnel into prepared jars. Wipe rims, apply lids and rings, and process in a boiling water bath canner for 10 minutes.

When time is up, remove jars from the canner and set them to cool on a folded kitchen towel.

Once jars are cooled, check to ensure jars sealed. Any unsealed jars should be refrigerated and used promptly.