Natural Black Tourmaline Stone 4.78 Carat (5.25 Ratti)

Natural Black Tourmaline Stone (Schorl) – 4.78 Carat (5.25 Ratti)

This Natural Black Tourmaline (known mineralogically as Schorl) weighs exactly 4.78 Carats (5.25 Ratti). Precision-cut and faceted into an elegant Oval Mixed Cut, this Earth-mined gemstone exhibits a deep, opaque pitch-black body tone with an immaculate vitreous surface polish and crisp facet junctions.

Mineralogical Identity & Physical Constants: Tourmaline is a complex cyclosilicate mineral with the generalized formula NaFe²⁺₃Al₆(BO₃)₃Si₆O₁₈(OH)₄, crystallizing in the trigonal crystal system. The Schorl variety is rich in elemental iron, producing complete opacity and deep black color. Under gemological testing, it displays a refractive index of 1.624 to 1.644 with uniaxial negative optical character, a specific gravity of 3.10 to 3.25, and a resilient Mohs hardness of 7.0 to 7.5. It exhibits natural pyroelectric and piezoelectric properties (generating subtle electrical charges under thermal or pressure variations).

Cultural & Modern Jewelry Context: Celebrated globally as an official birthstone for October (alongside Opal), Tourmaline has been revered for centuries across world traditions. Known in traditional Indian texts as Turmali, Black Tourmaline is favored for statement cocktail rings, pendants, and cuff links mounted in Sterling Silver (925 Silver), White Gold, or Platinum.

Please Note: Ratna Gems shares these historical, cultural, and gemological details solely for educational awareness. We sell all gemstones strictly on the basis of verified physical authenticity, mineral quality, and accredited laboratory certification, and make no astrological, metaphysical, or curative claims.

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