Place flour, black pepper, garlic powder, paprika, marjoram, salt, and cayenne pepper in a large plastic resealable bag and shake well to mix. Add scallops to the bag and toss to coat with flour mixture.
Heat olive oil in a large skillet over medium heat. Add all scallops in a single layer and sear until golden, 3 to 4 minutes per side. Drizzle balsamic vinegar over seared scallops.
