Bankok Neelam Stone 7.18 Ratti (6.53 Carat) - Blue Sapphire

Bangkok Blue Sapphire (Neelam) – 6.53 Carat (7.18 Ratti) Oval Mix Cut

This Bangkok Blue Sapphire (Neelam) weighs exactly 6.53 Carats (7.18 Ratti) with calibrated dimensions of 12 x 8.5 x 6 mm. Expertly faceted into a balanced Oval Mix Cut, this Earth-mined gemstone displays a deep, commanding blue hue, vitreous corundum luster, and balanced proportions ideal for fine jewelry mounting.

Mineralogical Identity & Physical Constants: Blue Sapphire is the precious blue variety of Natural Corundum (aluminum oxide, Al₂O₃), colored by intervalence charge transfer between trace titanium (Ti⁴⁺) and iron (Fe²⁺) substituting within the crystal lattice. Ranking at Mohs hardness 9 (second only to diamond), it offers superior scratch resistance and lifelong wearability. Under gemological testing, it exhibits a refractive index of 1.762 to 1.770 (birefringence 0.008, uniaxial negative), a specific gravity of 3.99 to 4.01, and a diagnostic trigonal crystal system.

Geographical Origin & Lapidary Profile: Cut and finished in Bangkok, Thailand—the premier international lapidary hub for colored gemstones—this sapphire exhibits excellent symmetry, balanced crown angles, and deep royal blue saturation. It has undergone traditional heat treatment, a permanent, widely accepted industry standard that stabilizes color and dissolves excess internal silk while preserving genuine natural corundum structure.

Cultural Legacy & Traditional Wearing: Known in Sanskrit as Neelam (नीलम) or Indraneel, Blue Sapphire holds a prominent position in Vedic astrology as the primary gemstone linked to Saturn (Shani). Traditionally, it is mounted in Sterling Silver (925 Silver), White Gold, or Panchdhatu for rings and pendants worn on the middle finger of the working hand on Saturday mornings during Shukla Paksha.

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.

Care Instructions

• Clean gently with lukewarm water, a mild dish soap solution, and a soft-bristled brush, then wipe dry with a lint-free microfiber cloth.
• Thanks to its Mohs 9 hardness, blue sapphire is exceptionally durable and resistant to scratching, but should still be stored separately from diamonds and other gemstones to prevent surface scuffs.
• Avoid contact with harsh industrial chemicals, strong acids, or sudden direct thermal shock. Ultrasonic cleaning is generally safe for untreated and heated sapphires unless heavily fractured.

Frequently Asked Questions