Bangkok Blue Sapphire

Approx. Rs 500 / CaratGet Latest Price

What “Natural Bangkok Blue Sapphire” Usually Means
Natural: The stone is mined from the earth — not synthetic. But “natural” does not guarantee untreated (i.e. no heat, clarity enhancement, filling, diffusion).
Blue Sapphire: Part of the corundum family. Color varies from light blue, medium blue, royal / deep blue, dark blue, etc.
Bangkok: This term can refer to either origin (the stone was mined in or near Thailand) or more often that the stone was cut, treated, or sold via Bangkok. Bangkok is a major gem trade and treatment center.
Neelam (in Vedic astrology): Refers to blue sapphire used as a remedy for Saturn (Shani). Stones used for astrological purposes often have additional requirements (purity, treatment disclosure, specific weight, etc.).
Key Properties & Specs to Check
Here’s what to examine/ask for when evaluating a “Natural Bangkok Blue Sapphire”:
PropertyWhat to Check / Good Range
Carat weightLarger stones cost exponentially more. Also, stones above a certain size (e.g. ~2-3 ct) are more likely to show imperfections, so cut & clarity become very important.
ColorA good blue sapphire has a rich, pure blue (or slightly violet or cornflower). Avoid excessive grey, green, or overly dark tones that kill brilliance. Bangkok sapphires often lean darker.
ClaritySome inclusions are acceptable and expected (e.g. rutile needle inclusions), but avoid large cracks or fractures, especially ones that are visible to the naked eye.
Cut / ShapeFaceted cuts bring out brilliance; shapes like oval, cushion, mixed cut are common. Good proportion and polish matter.
Origin & TreatmentOrigin: If truly from Thailand or nearby region, but check lab report. Treatment: Heat treatment is common and often acceptable; glass filling, diffusion, bleaching etc. are less preferred, especially for astrology. Untreated or minimally treated stones are more valuable.
Hardness, DurabilitySapphires are 9/10 on Mohs scale. Good toughness. But fillings or fractures reduce durability.
CertificationFrom a recognized gemological lab (GIA, GIT, IGI, GRS, or local respected labs). Certificate should specify origin (if possible), treatment (if any), weight, color, cut, clarity, etc.
Typical Examples / Market Specimens
Here are some real listings that illustrate what you might expect (values, specs, treatments). Useful to see what “Natural Bangkok Blue Sapphire” stones often look like in the market.
Luverra Gems: Natural & untreated Bangkok blue sapphire, 4.75 carat, with lab certification. (Neelam stone)
Ratna Gems: Stone of ~6.32 carat, oval mix cut, from Bangkok. Refractive index ~1.76-1.77. Good example of a mid-to-higher carat stone.
Tanishq Gems: 5.50 carat Bangkok blue sapphire, but glass-filled treatment disclosed. Shows that even big brands use treated stones, and disclosure matters.
Glass Filling / Resin Filling: Fills fractures with glass/resin. Makes the stone appear more flawless, but affects durability & value. Should be disclosed. E.g. the Tanishq 5.50 ct stone is “glass filled”.
Diffusion Treatment: Adding coloring agents to surface under high heat. Sometimes hard to detect; can be less stable or less valued.
“Origin” Labeling Can Mislead: Saying “Bangkok sapphire” may mean the stone was cut or treated there, not necessarily mined locally. Always check the lab report.
Good color, clarity, untreated, mid carat (≈3-7 ct) fetch much higher rates.