Step 1Cover raisins with hot water and let stand 5 minutes. Drain, then coarsely chop. Place in bowl with frozen blueberries.
Step 2Whisk together melted butter, oil, honey, brown sugar, egg, orange juice, orange oil, and lime and orange zests in large bowl.
Step 3Combine unbleached flour, whole-wheat flour, baking powder, baking soda, cinnamon, salt and caraway seeds in another mixing bowl. Fold flour mixture into egg mixture, stirring well. Gently fold in blueberries and raisins and mix thoroughly.
Step 4Spoon batter into 2 (7x3-inch) loaf pans, 2 (7- or 8-inch) cast-iron skillets or 1 (9-inch) springform pan coated with nonstick cooking spray. Sprinkle with oatmeal. Bake at 375 degrees until toothpick inserted in center of bread comes out clean, 35 to 45 minutes, 50 to 60 minutes if using loaf pans. Cool in pans 15 minutes, then turn onto cake rack to finish cooling.
Step 1Stir together powdered sugar, orange juice and zests to make soft glaze. Drizzle over cooled cakes. Apply decorative shreds of zest. (Can be frozen.)