Emeralds

Emeralds are precious green gemstones valued in both the Muggle and Wizarding world. Within the magical community, they are most famously used for decorative purposes and as a means of representing wealth and status. The gemstone carries a powerful and often dualistic symbolism, being strongly associated with Slytherin house and the dark magic of Lord Voldemort, while also being the defining feature of Lily Potter's eyes, a symbol of her protective love for her son, Harry Potter.

Emeralds appear in several significant contexts throughout the series, primarily linked to the legacy of Salazar Slytherin and the life of Harry Potter.

• Symbol of Slytherin House
  • The primary gemstone representing Slytherin house is the emerald, corresponding with its house colour of green. This is most visibly demonstrated by the House Point Hourglasses located in the Great Hall of Hogwarts, where giant emeralds fall from the top bulb to the bottom to signify points awarded to Slytherin.
  • Salazar Slytherin's Locket, one of Lord Voldemort's Horcruxes, was a heavy gold locket decorated with a serpentine 'S', which was inlaid with “small, green stones.” Given the locket's origin and serpentine motif, these stones are understood to be emeralds.
• Association with Lord Voldemort
  • As the Heir of Slytherin, Lord Voldemort's connection to emeralds is an extension of his heritage. He chose Salazar Slytherin's Locket as a Horcrux, a vessel for a fragment of his soul.
  • The basin in the crystal cave containing the locket Horcrux was filled with a mysterious, glowing potion described as “emerald green.” This potion, which had to be drunk to retrieve the locket, caused the drinker to experience terrible visions and intense pain, directly linking the emerald colour to Voldemort's cruel and powerful dark magic.
• The Eyes of Lily and Harry Potter
  • In stark contrast to its association with Slytherin, the colour emerald is most famously used to describe the eyes of Lily Potter. Her “brilliantly green,” almond-shaped eyes were her most memorable feature.
  • Harry Potter inherited his mother's eyes, a fact that is a constant, poignant reminder of her sacrifice to those who knew her, including Horace Slughorn, Remus Lupin, Sirius Black, and most notably, Severus Snape.
  • This shared feature symbolizes the enduring power of Lily's love, which gave Harry magical protection against Lord Voldemort. The final moments of Severus Snape's life were spent gazing into Harry's eyes, a last connection to the woman he had loved.

• In the film adaptations, the green stones on Salazar Slytherin's Locket are clearly depicted as faceted emeralds. (film)
• The visual aesthetic for Slytherin-related sets in the films, such as the Slytherin Dungeon, frequently uses emerald green lighting to reinforce the house's signature colour. (film)
• J.K. Rowling has explained the symbolic duality of the colour green. She chose it for Harry's eyes to connect him to his mother, but also acknowledged that green is often associated with malevolence, sickness, and Dark Magic (e.g., the light of the Avada Kedavra curse and the Dark Mark), reflecting the constant battle between good and evil, and love and death, within the series. (J.K. Rowling interview)