Cut the fish into 1 in / 2.5 cm. cubes, or leave the scallops whole, if using them. Heat the juice and marmalade together in a saucepan, and then strain it into a bowl. Mix in the sesame oil, soy sauce, seasoning and spices, and stir in the fish until it is well coated. Leave to marinate for 30–40 minutes. Thread the fish on to skewers, and cook under a moderately hot grill for about 8 minutes, turning and basting with marinade from time to time. When done, arrange the skewers on individual plates, sprinkle with the toasted sesame seeds and garnish with herbs and fruit.