In a large bowl, toss the apples with the lemon juice and zest, 3/4 cup sugar, cinnamon, salt and mace. In 2 large skillets, melt the butter. Add the apples and any accumulated juices and spread them in each skillet in a single layer. Cook the apples over moderate heat for 5 minutes, stirring occasionally, until lightly browned in spots. Add 1/4 cup of the apple cider to each skillet, cover and cook, shaking the pans occasionally, until the apples are tender, about 5 minutes. Remove the lids and let the apples cool. If the juices are not thick and syrupy, simmer uncovered for 2 to 3 minutes longer. Let cool completely.