How to identify Jadeite

To correctly identify Jadeite (Na(Al,Fe3+)Si2O6), check each of these features in order. Many rocks and minerals look alike, so cross-reference multiple properties before deciding.

Step-by-step identification

1. 1

   Color

   Overall color and any zoning or banding

   Ranges from white, gray, and pale green to dark green, blue-green, lavender, pink, brown, and black. The most prized color is an intense, translucent emerald green (Imperial Jade) due to trace chromium.

2. 2

   Luster

   How the surface reflects light: metallic, vitreous, dull

   Vitreous to greasy, sometimes pearly on cleavage surfaces.

3. 3

   Texture

   Grain size and surface feel: coarse, fine, glassy

   Typically fine-grained, interlocking granular aggregates, giving it a smooth, waxy feel when polished. Can be massive or fibrous.

4. 4

   Crystal Form

   Shape of visible crystals or crystal faces

   Rarely found as distinct crystals; usually occurs as dense, compact, interlocking aggregates of microscopic grains. When crystals are present, they are typically prismatic.

5. 5

   Cleavage

   How it breaks: flat cleavage planes vs irregular fracture

   Two distinct cleavages at nearly 90 degrees (pyroxene cleavage), but rarely observed in massive material due to its fine-grained, interlocking nature. Fracture is more common.

6. 6

   Geological Environment

   The rock formation and setting where it occurs

   High-pressure, low-temperature metamorphic rocks (blueschists, eclogites) in subduction zones. Also found in serpentinite-associated metasomatic deposits and alluvial placers derived from these primary sources.

Key Facts

Hardness

6.5-7 on the Mohs scale.

Specific Gravity

3.30-3.38 (higher than nephrite).

Crystal System

Monoclinic.

Color

White, green, lavender, blue-green, pink, brown, black. Often mottled or variegated.

Luster

Vitreous to greasy, sometimes pearly.

Transparency

Translucent to opaque, rarely semi-transparent.

Fracture

Splintery to uneven, due to its interlocking granular structure.

Cleavage

Perfect on {110} and {110} at nearly 90 degrees, but rarely observed in massive material.

Composition

Sodium aluminum silicate with variable iron: Na(Al,Fe3+)Si2O6.

Physical characteristics

• Crystal Habit: Typically massive, granular, or fibrous aggregates. Rarely as distinct prismatic crystals.
• Cleavage Type: Perfect prismatic cleavage at approximately 87 and 93 degrees, but usually not visible in massive material.
• Fracture Type: Splintery to uneven, conchoidal in rare instances.
• Tenacity: Extremely tough (resistant to breaking and chipping), making it highly durable.
• Luster Type: Vitreous to greasy, sometimes waxy on polished surfaces.

Explore Jadeite