Sapphires

• Type: Precious Gemstone
• Color: Blue
• Symbolism: Strongly associated with Ravenclaw House at Hogwarts School of Witchcraft and Wizardry.

Sapphires are valuable, blue gemstones that appear in the wizarding world primarily as decorative elements and as symbols of Ravenclaw House. They are noted for their beauty and value, similar to their status in the Muggle world. Their use is most prominent in two key areas: tracking House Points at Hogwarts and as the reputed gemstones on Rowena Ravenclaw's lost diadem. There is no canonical information detailing any specific magical properties inherent to sapphires themselves beyond their use in these enchanted contexts.

Sapphires are mentioned in two significant contexts within Hogwarts School of Witchcraft and Wizardry.

In the Great Hall at Hogwarts, four giant enchanted hourglasses are used to display the current standings of the four houses in the competition for the House Cup. Each hourglass is filled with different precious stones that represent the House Points earned by students. The hourglass for Ravenclaw House is filled with hundreds of blue sapphires. For every point a Ravenclaw student earns, a sapphire magically falls from the top bulb to the bottom; for every point lost, a sapphire returns to the top. The other hourglasses contain rubies for Gryffindor, topazes for Hufflepuff, and emeralds for Slytherin.

The legendary Diadem of Ravenclaw, a lost artefact created by Rowena Ravenclaw, was widely reputed to be set with sapphires.

• When Harry Potter sought the diadem as a potential Horcrux, he was told by Luna Lovegood that it was a “tiara set with sapphires” according to its historical description.
• The ghost of Helena Ravenclaw, daughter of Rowena, described the original diadem to Harry as having been set with “blue and white stones.”
• The actual, defiled diadem that Harry Potter found in the Room of Requirement—which Voldemort had turned into a Horcrux—is described as a delicate silver tiara with a “single blue-green stone, the size of a small egg” set in its center.

This discrepancy suggests that the legend of the diadem specified sapphires, while the physical reality of the object, at least in its corrupted state, was slightly different.

• In the film adaptation of Harry Potter and the Deathly Hallows: Part 2, the Diadem of Ravenclaw is depicted with multiple blue stones that resemble sapphires, more closely aligning with Luna Lovegood's description of the legend than with the book's description of the Horcrux that Harry finds (film).
• The House Point hourglasses are also shown in the films, with the Ravenclaw hourglass containing blue gems consistent with sapphires (film).