An opal is a mineraloid composed mostly of silica and water. Opals can express every colour in the visible spectrum, although the most common colours are white and/or green.

While tidying up the cabinets next to the mantelpiece at 12 Grimmauld Place in 1995, Harry Potter came across a large blood-filled crystal bottle with a large opal set into the stopper.^[1] There was a cursed opal necklace for sale at Borgin and Burkes that Draco Malfoy purchased and gave to and Imperiused Katie Bell in an attempt to assassinate Albus Dumbledore.

Appearances

• Harry Potter and the Chamber of Secrets (film) (Shortly seen in Borgin and Burkes)
• Harry Potter and the Order of the Phoenix
• Harry Potter and the Half-Blood Prince
• Harry Potter and the Half-Blood Prince (film)
• Harry Potter and the Half-Blood Prince (video game)

Notes and references