Burmese Blue Sapphire 1.18ct | Untreated | Mogok Origin | UK

A 1.18ct natural untreated blue sapphire from Mogok, Myanmar — untreated with slight inclusions. At over 1ct in a genuine Mogok blue, with no heat treatment, this stone represents a category of sapphire that is genuinely scarce in the UK market. The colour is natural and the 6.1 × 5.6mm face-up gives good presence for its weight.

Product Details

• Colour: Blue
• Weight: 1.18ct
• Origin: Mogok, Myanmar
• Clarity: Slight Inclusions (AA)
• Dimensions: 6.1 × 5.6 × 3.6mm
• Mineral: Natural Sapphire (Corundum)
• Hardness: 9 (Mohs scale)
• Treatments: None
• Product Code: J002

Our Clarity Grading

• AAA+: Loupe-clean
• AAA: Eye-clean (no inclusions visible to the naked eye)
• AA: Slight inclusions
• A: Moderate inclusions

Why Untreated Mogok Sapphire?

Heat treatment is the standard in the sapphire trade — an estimated 90–95% of blue sapphires on the market have been heated to improve colour and transparency. Untreated natural blue sapphire with Mogok provenance is a different category of material entirely. The colour is what the stone naturally produces, the hardness of 9 makes it the most durable of all coloured gemstones, and the Mogok origin carries historical and commercial weight that other origins do not match. For jewellers building bespoke engagement ring briefs and collectors who care about provenance, this is a serious stone.

About Natural Spinel Gem

We specialise in natural untreated spinel, sourced directly from small-scale miners in Mogok, Myanmar — one of the world's most celebrated gem origins. Gemstones are hand-cut locally. All gemstones are available for private viewing across London at your business premises or by appointment at Hatton Garden.