Complex sentence: They are often only used for the coronation of a monarch and a few other ceremonial occasions, though the monarch may also be often shown wearing them in portraits, as they symbolize the power and continuity of the monarchy.
Split into simpler sentences: They are often used for the coronation of a monarch and a few other ceremonial occasions. A monarch may often be shown wearing them in portraits, as they symbolize the power and continuity of the monarchy.