Peel pears; cut into halves; and core.
Treat to prevent darkening.
Rinse and drain.
Cover one layer of pears at a time with water and simmer over low heat 5 minutes.
Combine 4 cups water and 2 cups sugar in a sauce pot.
Simmer until sugar dissolves, stirring frequently.
Pack pears hot into hot jars, leaving 1/4-inch head space.
Add 1 tablespoon almonds to each jar of pears.
Remove sugar syrup from heat; stir in almond liqueur.
Pour hot over pears, leaving 1/4-inch head space.
Remove air bubbles.
Process 20 minutes in boiling water bath.