Green Tourmaline Goonbarrow China Clay Pit Cornwall Genuine Crystal with Certificate of Authenticity

Genuine Green Tourmaline – Goonbarrow China Clay Pit, Bugle, Cornwall, UK

This Green Tourmaline specimen from Goonbarrow China Clay Pit, Bugle, Treverbyn, Cornwall, England, is a genuine British crystal carefully selected for its colour, crystal habit and notable locality. The photograph provided shows the exact specimen you will receive. Please refer to the images for full sizing details and accurate scale.

This crystal includes a Certificate of Authenticity lifetime guarantee generic card confirming its genuine origin and mineral identification.

Mineral & Geological Classification – Green Tourmaline

Green Tourmaline belongs to the Tourmaline Supergroup, a complex family of boron silicate minerals. Most green specimens from granitic environments are classified as Elbaite, a lithium-bearing tourmaline species, although chemical variation is common due to elemental substitutions within the crystal lattice.

Mineral Group: Tourmaline Supergroup
Common Species: Elbaite (Lithium-rich Tourmaline)
Chemical Structure: Complex boron aluminium silicate
Crystal System: Trigonal
Hardness: 7–7.5 on the Mohs scale
Lustre: Vitreous
Transparency: Transparent to translucent

The green colour is typically caused by trace amounts of iron or chromium incorporated during crystal growth. Tourmaline crystals commonly form elongated prismatic structures with distinctive vertical striations along their length, reflecting their trigonal symmetry.

Cornwall Locality – Goonbarrow China Clay Pit

Goonbarrow China Clay Pit lies within the St Austell granite district of Cornwall, part of the larger Cornubian Batholith. This granite intrusion formed during the late Carboniferous to early Permian periods and is renowned for producing a diverse suite of mineral species.

The region’s china clay workings expose highly altered granitic pegmatites and hydrothermal veins. These pegmatitic bodies are enriched in rare elements such as lithium, boron and fluorine, creating ideal conditions for tourmaline crystallisation. Green tourmaline from this locality formed as mineral-rich fluids cooled within fractures and cavities in the granite.

Associated minerals in the area may include quartz, feldspar, mica, cassiterite and other tin-bearing minerals, reflecting Cornwall’s historic tin mining industry.

Crystal Characteristics & Notable Traits

Green tourmaline crystals typically display:

• Elongated prismatic growth

• Prominent vertical striations

• Rich green to olive or forest-green tones

• Transparent to translucent sections

• Vitreous, glass-like lustre

Natural inclusions, internal zoning and minor contact points are part of the crystal’s geological formation. Colour zoning may occur where trace element concentrations shifted during growth. In some specimens, subtle pleochroism may be visible, with slight colour variation when viewed from different angles.

Each crystal’s structure and surface detail reflect the pegmatitic environment in which it formed.

Geological Importance & Collectibility

Cornish tourmaline specimens are highly regarded among mineral collectors due to the region’s geological complexity and historic mining legacy. Goonbarrow China Clay Pit is a recognised locality within the St Austell granite district, adding provenance value to this specimen.

Tourmaline’s durability, distinctive trigonal crystal habit and vibrant green colour make it a desirable addition to mineral cabinets and educational collections. British locality specimens are especially sought after by collectors who value documented origin.

Because this is a genuine natural specimen, each piece displays unique growth features and internal characteristics. The photograph shows the exact crystal you will receive.

Authenticity & Presentation

This Green Tourmaline specimen from Goonbarrow China Clay Pit has been carefully chosen for quality, locality and presentation. Included with your purchase is a Certificate of Authenticity lifetime guarantee generic card confirming its genuine origin from Cornwall, England, UK.

Combining classic Cornish granite geology with the striking prismatic form of tourmaline, this Green Tourmaline specimen offers mineral authenticity, regional heritage and collector appeal in one carefully selected crystal.