Wash the peaches thoroughly under cold running water, peel off the skin, cut them in half to remove the pits, and slice them into smaller pieces.

In a large, heavy-bottomed pot, combine the sliced peaches with the granulated sugar and lemon juice, stirring well.

Place the pot over medium-high heat, stirring frequently, and bring the mixture to a full rolling boil.

Keep boiling until the mixture thickens, then reduce the heat to low and let it simmer for about 15-20 minutes.

Skim off any foam that rises to the surface.

If not thick enough, continue cooking over medium heat, testing for thickness every 5 minutes.

While the preserves are cooking, wash canning jars and lids in hot, soapy water.

Use a ladle to pour hot peach mixture into hot jars, leaving ½ inch of headspace.

Remove air bubbles by running a spatula around inside of the jar.

Place filled jars into a water bath canner covered with at least an inch of water, bring to a boil, cover, and process for 10 minutes.

Once processed, cool jars on a clean towel or cooling rack.