The Emerald (Greek: σμάραγδος smaragdos "green gem")is one of the items that are necessary to solve the riddles surrounding the acquisition of the Key of Tears from inside Raysiel's Tower. In the game, the Emerald is representative of the colour Green.
This particular jewel can be picked from the exquisite stained glass window in the small Chapel in Raysiel's Tower. Along with six other gems, it has to be correctly placed according to the ROYGBIV colour spectrum on the star that has been etched on the floor. Completion of this riddle will yield us the Rainbow-coloured Key which is used for opening the door inside the Nightingale Floor Room, allowing us to retrieve the Coloured Gem from a small casket, required to access the shimmering walkway in the main hall of the Room of Riddles.
The Emerald reappears during our trials in Sheol, where we find it incorporated in one of the puzzles surrounding the Third Test to the Key of the Abyss.
The Emerald is a variety of Beryl (Be3Al2(SiO3)6) which owes its distinct green colour to traces of Chromium and sometimes also Vanadium. The English expression Emerald can be derived, via the Old French esmeraude and Middle English emeraude, from the Vulgar Latin esmeraldus, a variant of the Latin smaragdus that stems from the Greek σμάραγδος (smaragdos) "green gem".
While the Emerald is greatly appreciated as a gemstone and as such frequent incorporated by jewellers in rings, necklaces and other precious trinkets, astrology and folklore have also introduced some beliefs as to the qualities of the stone. As such, the Emerald is considered the birthstone for May and the traditional gemstone associated with the zodiac signs Taurus, Gemini and Cancer.
Emerald is also a stone of great vision and intuition, associated with the eyes and sight, long believed to foretell future events and reveal one’s truths. It is a stone of wisdom, enhancing memory and increasing mental clarity. It combines intelligence with discernment, and brings to the conscious mind what is unconsciously known. Emerald also increases focus and intent, activating psychic abilities and opening clairvoyance. Traditionally it was used as a protection against enchantment and spells.
Adam: I know this one. It's an Emerald.