Sapphire is a precious gemstone that is most commonly known for its striking blue color, although it can actually be found in a wide range of colors, except for red (which is classified as ruby). Sapphires are composed of corundum, a mineral made of aluminum oxide, and their brilliance and clarity are highly valued in the jewelry market.

Key characteristics of sapphires include:

1. Color: The most prized sapphires are deep blue, but they can also come in pink, yellow, green, and even colorless varieties. The hue, tone, and saturation all contribute to the stone's overall quality.

2. Hardness: Sapphires are very hard, scoring a 9 on the Mohs scale of mineral hardness, making them an excellent choice for everyday wear.

3. Clarity: High-quality sapphires are typically very clear, though some may have inclusions. The presence of certain inclusions can even enhance their value, such as the silk inclusions that create a star effect in star sapphires.

4. Brilliance: When properly cut, sapphires can exhibit exceptional brilliance and sparkle, which adds to their allure.

5. Symbolism: Sapphires are often associated with wisdom, loyalty, and nobility, making them a popular choice for engagement rings and other significant jewelry pieces.

If you have any specific questions or need more detailed information about sapphires, feel free to ask!