1. In a large bowl, combine the pears, lemon juice and peel and coriander. Add 1/2 cup sugar; toss gently to coat. Spoon into pie shell. In a small bowl, combine the flour, cinnamon, mace and remaining sugar; cut in butter until mixture resembles coarse crumbs. Sprinkle over pears.
2. Bake at 400° for 45 minutes or until filling is bubbly and topping is browned. Cool on a wire rack. Serve warm or cold with ice cream if desired. Yield: 6-8 servings.