Because of their long use and simple outline, roundels are accorded status as a subordinary charge by most heraldic writers.
Roundels in British heraldry have different names depending on their tincture. Thus, while a roundel may be blazoned by its tincture, e.g., a roundel vert (literally "a roundel green"), it is more often described by a single word, in this case pomme (literally "apple", from the French) or, from the same origins, pomeis — as in "Vert; on a cross Or five pomeis" (Scottish Public Register vol. 32, p. 26).
In French blazon, a roundel of either metal (or or argent) is a besant, and a roundel of any colour (dark tincture) is a torteau, with the tincture specified.
One special example of a named roundel is the fountain, depicted as a roundel barry wavy argent and azure, that is, containing alternating horizontal wavy bands of blue and silver (or white). Because the fountain consists equally of parts in a light and a dark tincture, its use is not limited by the rule of tincture as are the other roundels. Another name for the fountain is the syke (Northern English for "well").
Another special roundel, largely confined to Scots heraldry, is the gurges filled with a double spiral of contrasting tinctures, usually drawn as a symmetric parabolic spiral such as Fermat's Spiral using the polar equation r^2=a^2*theta, although any variety of spiral form may be displayed. The gurges derives from ancient and prehistoric spirals which represented tripartite power: sovereignty, force and fecundity. The spiral can be seen in many aspects of nature such as the arrangement of leaves along a stem or florets within a composite flower head. A gurges argent and azure usually represents a whirlpool, yet can be seen in the arms of the former James Watt College representing the force of steam within a Watt steam engine. Because the chief was azure, the gurges was displayed as an Archimedes' Spiral drawn using the polar equation r=a*theta, which in the official blazon is referred to as a spiral argent.
In their earliest uses, roundels were often strewn (semy) upon the field of a coat of arms, a design with as many names as there are tinctures. For example, a field semy of roundels argent could be called platy; a field semy of roundels sable could be called pellety. The precise number and placement of the roundels in such cases were usually left to the discretion of the artist.
- Fox-Davies, Arthur Charles (1909). A Complete Guide to Heraldry. p. 151.
- Fearn, Jacqueline (1980). Discovering Heraldry. Shire. p. 25.
- http://www.dsl.ac.uk/entry/snd/syke Scottish National Dictionary of 1700: syke
- http://mathworld.wolfram.com/FermatsSpiral.html Wolfram MathWorld: Fermat's Spiral
- https://books.google.com/books?id=qWCMNelFmXIC&pg=PA28&lpg=PA28&dq=symmetric+parabolic+spiral&source=bl&ots=hoq65iCR7I&sig=2juWUPMS8rA772mJe56NbBV85hc&hl=en&sa=X&ei=pQQ6Vcz1L-aHsQSMmICABA&ved=0CDIQ6AEwAw#v=onepage&q=symmetric%20parabolic%20spiral&f=false Symmetry: The Ordering Principle. By David Wade. Bloomsbury Publishing USA, Oct 17, 2006 - Mathematics - 58 pages. Page 28.
- http://mathworld.wolfram.com/ArchimedesSpiral.html Wolfram MathWorld: Archimedes' Spiral