Ancient rubies were generally made into amulets by ancient peoples to guard against poisons, plague, evil thoughts, and wicked spirits. A long-held persistent belief is that rubies warned of the presence of poison by growing dark and cloudy, and then resumed their brilliance when the danger was past. Some writers extended rubies ability to warn of any danger which threatened the wearer.
Relative to that notion, the 14th century Italian poet Francesco Petrarch recounted that the French king, John II was not protected by a ruby ring when he was captured by the English in 1356 at the Battle of Poitiers. Years later, when the king was reunited with his ring, Petrarch wrote that he was pleased, “…to see an object of infinite value and beauty but of no use whatsoever!”
Other writers have stressed the power of ruby to keep its wearer in health and keep his mind cheerful. In 1669 Dr. J. Schroeder wrote: “You may try the goodness of the Rubine (the German word for ruby) by the mouth and tongue; for the coldest and hardest are the best…. it resists poison, sadness, frightful dreams, clears the mind, keeps the body safe, and, if mischance be at hand, it signifies this by turning of a darker color…”
In many parts of the world, the wearer of a ruby was believed to be blessed with health, wealth, wisdom and outstanding success in affairs of the heart.
An ancient legend relates: “If the four corners of a house, garden, or vineyard were touched with ruby, they would be preserved from lightning, tempest and worms… ” The wearer of a ruby acquired the magic ability to live in peace with his enemies, providing a ruby ring was worn on the left hand or a ruby brooch on the left side.