Moonstone Flame — Blue Adularescence Feldspar

Moonstone Flame — Blue Adularescence Feldspar (9cm)

A polished moonstone flame displaying vivid blue adularescence, caused by light interacting with internal feldspar layers. The flash moves across the surface as the angle changes, creating a shifting electric-blue sheen.

This piece shows clear lamellar structure, visible as fine internal layering — the key feature responsible for the optical effect.

The flame cut enhances the movement of light, making this a strong display piece from multiple angles.

Key Features

• Mineral Type: Feldspar (Orthoclase–Albite intergrowth)

• Chemical Formula: KAlSi₃O₈ – NaAlSi₃O₈

• Formation: Slow cooling → separation into layered feldspar phases

• Colour: Grey, cream, brown with blue optical flash

• Transparency: Translucent to semi-opaque

• Lustre: Vitreous to pearly

Feature Highlights

• Noticeable blue adularescence across main face

• Visible internal layering (lamellar structure)

• Flame shape enhances light movement and display

• Natural internal fractures and textures throughout

• High-polish finish

• Untreated — optical effect, not artificial colour

Dimensions

• Weight: 150 grams

• Size: 9 cm x 5.5 cm

Geological & Scientific Notes

Moonstone forms from an intergrowth of orthoclase and albite feldspar.

During cooling, these minerals separate into extremely thin layers. When light enters the stone, it scatters between these layers, producing the glow known as adularescence.

The blue flash is caused by light interference, not pigment.

The intensity depends on: • Layer thickness

• Cut orientation

• Viewing angle

Condition

• Excellent polish

• Natural internal fractures (typical of feldspar)

• No structural damage