13 Sided Tridecagons
The tridecagon is a polygon with 13 sides and angles. It is also called a triskaidecagon. There are 5 regular tridecagon shapes given by Schlafli symbol. three of which resemble star shapes. The arrangement of stars on this 1817 Matron or Coronet Head 1 cent coin gives a good example of the 13 sided tridecagon.
Visit wikipedia.org tridecagon (geometry) for more detailed information about the tridecagon shape.