Cut each apricot into 8 slices.
In a mixing bowl, combine the unpeeled apricots, lemon juice and sugar. Cover and set aside for 12 hours.
Transfer apricot mixture to a pot, and bring to a boil. Simmer for 25 minutes.
Remove the foamy top while cooking. Remove the fruit from the syrup with a skimmer and transfer to a bowl. Set aside.
Boil the syrup until thickened. Add reserved apricots and almonds to syrup. Cook over low heat for 5 minutes while gently stirring the preserves.
Allow to cool before transfering to jars