Perhaps one of the most recognizable indicators of a royal is her headwear.
What’s the difference?
Fascinators usually have less of a practical purpose and are more decorative.

The headgear also denotes social standing.
Apparently, high-quality head coverings are difficult to imitate (viaBustle).
She continued, “For most people, the hat is quite serious and frivolous at the same time.

It completes the outfit and it’s a finishing touch.”
There are even rules for which hats go with different hemlines.