The Probert Encyclopaedia of Heraldry

GULES

Gules is the heraldic name for the colour red. It ranks highest among the colours. It is indicated in seals and engraved figures of escutcheons by parallel vertical lines. Because of its heraldic connection. the word gules is used poetically for a red colour or that which is red. Gules ranks after the metals or and argent, and has the highest place among colours.
Research Gules