Corundum · Chromium red
Ruby
The red of kings.
This stone has been sold. Ask us about similar material.
SoldCertified · traceable origin
Typical size: 1 – 5 ct · Price on request
SoldSpecifications
- Mineral family
- Corundum
- Composition
- Al₂O₃ : Cr
- Hardness (Mohs)
- 9
- Refractive index
- 1.762 – 1.770
- Crystal system
- Trigonal
- Colour
- Red to purplish red, coloured by chromium
- Typical origins
- Mozambique · Myanmar · Tanzania
Specifications are general gemological references for the species; each stone is assessed and documented individually.
Origin & story
Ruby is the red variety of corundum, its colour born from traces of chromium locked into the crystal as it formed under intense heat and pressure. Fine ruby is among the rarest of all coloured stones.
East Africa — including Mozambique, Tanzania, and Kenya — has become one of the world's most important sources of gem ruby. SOMSTONE evaluates rough and cut ruby for colour saturation, clarity, and traceable origin.
Documentation
What to expect from a lab report
Where appropriate, stones are submitted to an independent gemological laboratory. A typical identification report records the fields below; values shown here are placeholders for illustration only and do not describe a specific stone.
Illustrative only. Not an actual certificate. Reports are issued by independent laboratories on a per-stone basis.
Sample — illustrative layout
Specifications · Ruby
Report no. SAMPLE-000000
Date DD · MM · YYYY
- Identification
- Corundum
- Variety
- Ruby
- Weight
- —.— ct
- Dimensions
- —.— × —.— × —.— mm
- Shape / cut
- —
- Colour
- Red to purplish red, coloured by chromium
- Transparency
- Transparent
- Origin opinion
- Subject to laboratory analysis
- Treatment
- Subject to laboratory analysis
- Comments
- Issued with stone-specific measurements and photographs.
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Buyer questions
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