Sprinkle tuna with rosemary, salt and pepper. Add half oil and butter to large pan. Add tuna and cook 2 mintues on each side. Remove and set aside. Add remaining butter and oil. When hot add mushrooms, garlic, marjoram, salt and pepper. Cook 10 minutes. Add wine and parsley, bring to simmer cook 1 minutes. Return tuna to skillet. Baste with mushroom sauce.