Scarlet Shade

Color

Gemstones are evaluated based on their color, which is assessed through three factors: hue, tone, and saturation. Hue pertains to the gradation of color, like light or dark. Tone describes the degree of light absorption and reflection, determining the stone’s color intensity; for instance, dark stones absorb light while lighter ones reflect it more. Saturation measures the color’s intensity in gemstones.

Deep red garnets are the most common and favored, yet garnets also come in colors such as orange, brown, yellow, pink, green, blue, and even colorless. Rare garnet colors include peach, green, colorless, and blue.

Before exploring garnet color variations, understanding that garnets are classified into two groups: calcium garnets and magnesium garnets, is beneficial. Within these two groups are six varieties: almandine, pyrope, spessartite, grossular, andradite, and uvarovite. Each type is known for its unique color.

• Almandine: This garnet type contains aluminum silicate, giving it a deep red color with a violet tint.
• Pyrope: This abundant garnet type ranges from purplish-red to deep blood-red. It’s a magnesium or calcium aluminum silicate and is relatively inexpensive due to its commonness.
• Rhodolite: Known for its rose-red or purple-red hue, this garnet usually lacks visible flaws and inclusions.
• Spessartite: Varies from fiery orange to reddish-brown, resembling cinnamon.
• Grossularite: A mix of aluminum and calcium, this type includes three subcategories:
  • Tsavorite: A highly valued garnet with a green or emerald green hue.
  • Hydrogrossular: Opaque and greenish.
  • Leuco: A colorless variety.

Hue, Tone & Saturation

Garnets are celebrated for their rich, dense hues. Hue refers to the stone’s position on the color wheel, a visual representation of primary, secondary, and tertiary colors. Garnets stand out for their wide range of colors, from colorless to orange to green to deep red.

Saturation in garnets varies with the hue. Due to the range of garnet types with different colors, saturation levels can differ. Each garnet is unique, and examining both hue and saturation is essential when evaluating them.

Opacity

While garnets are primarily noted for their color, their clarity is also vital, especially in lighter stones. Understanding garnet opacity involves recognizing two groups: calcium garnets and magnesium garnets, each with six categories (almandine, pyrope, spessartite, grossular, andradite, and uvarovite). Garnet clarity varies by type; for example, almandine, pyrope, and rhodolite typically lack visible inclusions, while spessartite and hessonite often show eye-visible inclusions. Common inclusions like rutile needles can add unique traits to garnets:

• Hessonite: Displays distinct toffee-colored streaks, giving it an oily or glassy appearance.
• Grossular: Can contain dark gray to black inclusions.
• Star Almandine: Rutile inclusions reflect light, creating star-like shapes on the stone’s surface.

Treatment

Unlike most gemstones, garnets typically aren’t treated to enhance their color or clarity. They are unaffected by heat or irradiation, so they remain untreated. The rare and valuable demantoid garnet, usually green, is sometimes heat-treated to enhance its color.