Black Tourmaline Madagascar Natural Schorl Crystal Mineral Specimen 15-40mm Genuine Collector Display Stone with Certificate

Black Tourmaline – Natural Schorl Crystal from Madagascar

This genuine Black Tourmaline specimen from Madagascar is a natural variety of the mineral species Schorl, selected for its crystal form, surface texture, and collector appeal. Each piece measures approximately 15–40mm, making it ideal for mineral displays, geological collections, or decorative stone arrangements. The photograph shows an example of the actual specimen you will receive. Please refer to the listing images for full sizing and natural variation within this range.

Your Black Tourmaline includes a Certificate of Authenticity lifetime guarantee generic card, confirming it is a 100% genuine natural mineral specimen.

Mineral Species & Chemical Composition

Black Tourmaline is the common name for Schorl, a sodium iron aluminium borosilicate mineral belonging to the tourmaline group. Its complex chemical formula is typically expressed as:

NaFe₃Al₆(BO₃)₃Si₆O₁₈(OH)₄

Tourmaline minerals crystallise in the trigonal crystal system and are known for their elongated prismatic crystals with strong vertical striations.

Key mineralogical properties include:

• Mineral Group: Tourmaline (Cyclosilicate)

• Crystal System: Trigonal

• Hardness: 7–7.5 on the Mohs scale

• Lustre: Vitreous to subvitreous

• Transparency: Opaque

• Fracture: Uneven to subconchoidal

The black colour of Schorl results from its iron-rich composition.

Crystal Habit & Surface Characteristics

Black Tourmaline typically forms elongated, columnar crystals with distinctive vertical striations running along the length of the prism. In the 15–40mm size range, specimens may display:

• Strong linear striations

• Natural terminations

• Slightly irregular or intergrown crystal clusters

• Matte to glossy surfaces

Natural fractures and minor surface imperfections are part of authentic geological formation. No artificial dyes or enhancements have been applied.

Geological Formation – Madagascar Deposits

Madagascar is one of the world’s most significant sources of high-quality tourmaline specimens. Black Tourmaline commonly forms in:

• Granitic pegmatites

• Metamorphic rocks

• Hydrothermal vein systems

During the late stages of magma crystallisation, boron-rich fluids enable tourmaline formation. Iron-rich conditions lead to the development of Schorl rather than other coloured tourmaline varieties.

Black Tourmaline is frequently associated with quartz, feldspar, mica, garnet, and other pegmatite minerals. Madagascar’s geological diversity contributes to the formation of well-defined and collectible crystal specimens.

Collecting & Display Appeal

Black Tourmaline remains one of the most recognised and widely collected tourmaline varieties due to its distinctive form and strong geological identity. The 15–40mm size range makes these specimens ideal for:

• Mineral display cabinets

• Educational geology collections

• Collector gift pieces

• Decorative natural stone arrangements

• Study of trigonal crystal structures

In some traditions, Black Tourmaline is spiritually associated with grounding and protection; such associations are belief-based rather than scientific.

Authenticity & Individual Selection

Each Black Tourmaline specimen is carefully chosen for natural character and crystal structure. The listing photograph shows an example of the actual specimen you will receive within the stated 15–40mm size range. Please review all images for scale and natural variation.

Every piece includes a Certificate of Authenticity lifetime guarantee generic card, confirming its genuine natural origin from Madagascar.

A classic example of iron-rich tourmaline formation in pegmatitic environments, this Madagascan Black Tourmaline specimen offers geological significance, strong crystal definition, and excellent collector appeal in a versatile display size.