Mythology
According to one of the most famous Cretan Myths, Amalthia used to be the Goat that took care of Zeus. He was well hidden in the Psiloritis Range in a cave that was named as "Idaean Cave or Idaion Cave". His mother Rhea took him there as she was afraid of Saturn the King of Universe (Zeu's father) who used to swallow his male children so as to prevent them from being the following Kings of the Universe.
Amalthia would feed Zeus with milk and honey and with the help of The Bee and The Kourites (mythical creatures) were responsible for Zeus's brought up.
One day while young Zeus was playing along with Amalthia he broke her horn by mistake. For the sake of Amalthia Zeus transformed Amalthia's horn in a "cornucopia" or "horn of plenty". The owner of the horn of plenty would always be wealthy and it symbolizes the infinite state of Wealth that is offered to the humans by the Gods.
When Zeus was ready to compete for the absolute monarch, Ephaistos the God of Fire constructed a shield that was covered by Amalthia's skin. The shield was invincible and the outer part was covered by Medusa's head or by a mermaid. Anyone who would stare at it would turn into a stone. Zeu's shield was supposed to offer protection to the owner and anyone who would held it would always be protected. In the Greek culture there is a certain phrase that describes the state of being protected as "ΥΠΟ ΤΗΝ ΑΙΓΙΔΑ ΚΑΠΟΙΟΥ" that means "under the cloak of'".