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Ruby

📏 5.5 × 5.5 mm

⚖️ 1.08 ct

🌱 Natural ruby

Tanzania

Cut and finished in Sri Lanka

⭐️ This stone is untreated/unheated.

🤝 Responsibly sourced through Nineteen48's trusted supply chain

SKU TZ-RUB-000559
Original price £600.00 - Original price £600.00
Original price
£600.00
£600.00 - £600.00
Current price £600.00
Only one available

Responsibly sourced rubies from Sri Lanka and Tanzania. Rubies are corundum, and by definition, red, coloured by the presence of chromium.

Nineteen48 works directly with a trusted network of miners and suppliers to ensure all rubies are sourced through a fair and transparent supply chain.

Rubies are a popular gemstone, one of the "Big Three" of precious stones.

Red corundum is ruby, however there is no official classification for this. If you are looking for a red ruby or a pink sapphire, do broaden your search to look for both.

Nineteen48 rubies are responsibly sourced from Sri Lankan mines through a long-established network of local Sri Lankan miners, with whom strong and trusted relationships have been developed over the years.

The majority of the rubies here are from the Rubyfair project and were sourced from a community mine that operated near Mahenge in Tanzania. These stones have not undergone any heat treatment or other enhancements.

The Rubyfair project has now finished therefore the selection of Rubyfair gems on this website are the last remaining stones.

  • Tanzania

Tanzania has been a source of gemstones for decades. Most of the gem mining is either artisanal or small-scale (ASM). It is known for being the country where we find tanzanite, probably its most famous gemstone, which is much rarer than diamond. Other gemstones mined in Tanzania include sapphire, ruby, spinel and tsavorite garnet.

Miners often work in small teams using only hand tools, but there are also mines with some more advanced mechanisation. Gem mining has become an important part of the Tanzanian economy and mining overall is a significant employer, often providing income in communities where the opportunities to make a living are limited.

Gemstone mining in Tanzania is primarily overseen by the Ministry of Minerals and the Mining Commission, but there are also a number of other trade bodies and associations that represent the sector.

Gemmological Info

Ruby is by definition, red. When corundum is red, it is called ruby. There is no definitive rule that separates pink and red - it is up to the viewer to decide if the stone is a ruby or a pink sapphire.

Composition: Al₂O₃ (aluminium oxide)
Crystal system: Trigonal
Hardness: 9
Cleavage: None
Fracture:Uneven, conchoidal
Lustre: Adamantine, vitreous
Specific Gravity (SG): 3.90–4.10
Refractive Index (RI): 1.756–1.780
Birefringence: 0.008–0.010
Optical nature: Uniaxial (-)
Dispersion: .018