Symbol: The Twins
Phrase: I think
Archetype: The communicator, announcer, salesperson
Shadow: Intellectual superficiality
Day of the week: Wednesday
Main Lucky Gem: Agate
Gemini is related to duality and movement between opposite sides, thus being a bridge between the two. This Positive, Mutable and Air sign is sociable and outgoing, light and playful, but is easily bored and needs stimulation for his curious and agile mind.
If you want to know more about this sign, listen to the episode I am Gemini (Sun in Gemini) on the Millennial Astrology podcast: