Gemstone Guide
Sapphire
Enduring color, remarkable variety
Blue made sapphire famous, but corundum forms in almost every color — and in a range of qualities, treatments and origins that shape what a stone is worth. This guide covers what a collector should know, from the mine to the laboratory report.
- Species
- Corundum
- Hardness
- 9 on the Mohs scale
- Colors
- Every hue but red
- Key sources
- Sri Lanka, Myanmar, Madagascar
- Common treatment
- Heat
- Birthstone
- September
Sapphire is one of the world’s most recognized colored gemstones. Its name immediately suggests blue, but sapphire actually occurs in an extraordinary range of colors — from pink, yellow and green to purple, orange and colorless.
This combination of color, rarity and durability has made sapphire important in jewelry for centuries. It is equally suited to a meaningful piece of jewelry, a collection built around color, or the study of how origin, treatment and cutting can influence a gemstone’s appearance.
A Gemstone with a Long History
Sapphire belongs to the mineral species corundum. Red corundum is called ruby; corundum of every other color is classified as sapphire.
For centuries, blue sapphire has been associated with royalty, wisdom, loyalty and protection. It has appeared in religious objects, royal collections and important jewelry throughout the world. Today, it remains one of the most popular alternatives to diamond for engagement rings because it combines rich color with excellent durability.

Some of the most famous historic sapphires came from Kashmir, Myanmar and Sri Lanka. Each source developed its own reputation, but a sapphire’s origin should never be treated as a guarantee of quality. Mines produce a range of material, and beautiful sapphires can come from both historic and newer sources.
Where Sapphires Are Found
Sri Lanka — formerly called Ceylon — is one of the oldest and most important sapphire-producing regions. It is known for a broad spectrum of colors, including blue, pink, yellow, violet, color-change and padparadscha sapphires.
Myanmar has produced fine blue sapphires, often with strong saturation. Kashmir became legendary for a relatively brief period of production beginning in the late nineteenth century. The finest Kashmir stones are celebrated for a soft, velvety blue created partly by microscopic inclusions that scatter light.
Madagascar has become a major modern source and has produced sapphires capable of rivaling stones from traditional localities. Australia, Thailand, Cambodia, Tanzania and Montana in the United States are also important sources.
- Sri Lanka 8 in stock
- Myanmar
- Kashmir
- Madagascar
- Australia 1 in stock
- Thailand
- Cambodia
- Tanzania 1 in stock
- Montana 1 in stock
Origin can add historical interest and market value, but appearance comes first. A beautiful sapphire from a newer deposit may be more desirable than an ordinary stone from a famous location.

Understanding Sapphire Color
Color has the greatest influence on sapphire value.
The most sought-after blue sapphires generally display strong to vivid saturation, with a medium to medium-dark tone. If a sapphire is too dark, it may appear black or lose brightness. If it is too light or grayish, it may lack the depth associated with fine blue sapphire.
Uniformity also matters. Many natural sapphires contain color zoning — areas of lighter and darker color within the same crystal. Skillful cutting can position these zones so the gemstone presents an attractive and reasonably even face-up appearance.

Blue is only one part of the sapphire story. Sapphires that are not blue or red are commonly called fancy sapphires. These include:
- Pink sapphire
- Yellow and orange sapphire
- Green sapphire
- Purple and violet sapphire
- Color-change sapphire
- Colorless sapphire
- Padparadscha sapphire

Fancy sapphires in the collection
View the collection-
Distinguished — rated 36 of 50 on the Otzera 504.04 ct Tanzanian Color-Change Sapphire — GIA Origin Report
$6,495.00
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Distinguished — rated 40 of 50 on the Otzera 502.77 ct Unheated Australian Parti Sapphire — Radiant Cut
$4,925.00
-
Collectible — rated 33 of 50 on the Otzera 502.82 ct Natural Pinkish Purple Sapphire — GIA Report
$3,650.00
-
Collectible — rated 34 of 50 on the Otzera 501.37 ct Vivid Orange Sapphire — Oval Mixed Cut
$1,595.00
A color-change sapphire shows one color in daylight and another under warm indoor light. The shift comes from the way the stone absorbs light, and the stronger and cleaner the change, the more it is valued.


Padparadscha is a rare pinkish-orange to orange-pink sapphire whose name is associated with the color of a lotus blossom. Because the acceptable color range can be debated, a laboratory report is particularly important for a valuable stone sold under this name.
Clarity and Natural Character
Most natural sapphires contain some inclusions. These can include mineral crystals, needles, fingerprints, healed fractures, color bands and fine rutile silk.
Inclusions generally reduce value when they interfere with transparency, beauty or durability. However, not every inclusion is undesirable. Fine silk can soften the appearance of a sapphire and create the velvety quality associated with some highly valued stones.
Oriented needle-like inclusions can also produce asterism — the moving star seen in star sapphires. These stones are cut as cabochons rather than faceted gems. A fine star sapphire should display a well-centered, distinct star with rays that move smoothly as the stone is tilted.

Extremely clean natural sapphires are unusual. A stone that appears completely flawless should receive careful gemological examination, both to confirm its natural origin and to check for treatment.
Cutting Sapphire: Balancing Color and Weight
A sapphire cutter rarely begins with perfectly even rough. The crystal may contain zoning, inclusions and different colors when viewed from different directions.
The cutter must decide how to orient the gemstone to display its best color while retaining as much valuable weight as possible. This is why many sapphires are cut as ovals, cushions or mixed cuts: these shapes often follow the natural form of the rough efficiently.
A heavier sapphire is not necessarily a better sapphire. Excessive weight can be hidden beneath the girdle, where it contributes little to the face-up size or beauty. Conversely, a cut that is too shallow may allow light to pass through the center, creating a pale or transparent-looking “window.”


A well-cut sapphire should appear lively, balanced and attractive across most of its face.
From Mine to Collector
A sapphire’s journey begins with rough material recovered from primary rock deposits or secondary deposits such as river gravels.
The rough is sorted according to color potential, transparency, size and likely treatment response. Some material is sold without treatment, while other rough is heated before or after cutting. Cutting often takes place in established centers with specialized knowledge of corundum.
The finished gemstone may then be submitted to an independent laboratory to confirm whether it is natural or laboratory-grown, identify detectable treatments and, when requested and possible, provide an opinion on geographic origin.
At each stage — mining, sorting, treatment, cutting, testing and retail presentation — knowledge and judgment add value. Clear disclosure allows buyers to understand which part of that value comes from natural rarity and which part comes from human intervention.
The Gemology behind Sapphire Treatments
Heat Treatment
Heat is the most common sapphire treatment. It may improve color, reduce unwanted tones, dissolve or alter silk, and improve apparent clarity.
Traditional heating is widely accepted in the gemstone market when properly disclosed. Its results are generally stable under normal wearing conditions.
Because heat treatment is so common, a claim that a sapphire is unheated should ideally be supported by gemological proof.
Unheated sapphires in the collection
View the collection-
Distinguished — rated 36 of 50 on the Otzera 501.47 ct Unheated Yogo Sapphire — GIA Origin Report
$9,850.00
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Distinguished — rated 35 of 50 on the Otzera 502.73 ct Unheated Blue Sapphire — GIA Report
$4,950.00
-
Distinguished — rated 37 of 50 on the Otzera 501.57 ct Unheated Sri Lankan Purple Sapphire
$1,560.00
-
Collectible — rated 29 of 50 on the Otzera 501.03 ct Unheated Sri Lankan Blue Sapphire — Oval Mixed Cut
$895.00
Laboratory Reports and Origin
A colored-stone report can confirm:
- Whether the gemstone is natural or laboratory-grown
- Its weight, measurements, shape and cutting style
- Its color description
- Detectable treatments
- Geographic origin, when origin testing is requested and a conclusion is possible

A report does not replace visual judgment. Laboratories generally identify and describe colored stones rather than assigning them a universal quality grade.
Durability and Everyday Wear
Sapphire measures 9 on the Mohs hardness scale. It has excellent toughness and no cleavage, making it one of the most practical colored gemstones for daily-wear jewelry.
It can still chip if struck forcefully, especially along a thin girdle, exposed corner or surface-reaching fracture. Protective settings are advisable for stones with sharp points or visible durability concerns.
Cleaning and Care
Warm water, mild soap and a soft brush are safe for sapphire.
Ultrasonic and steam cleaners are usually considered safe for untreated and conventionally heat-treated sapphires. However, they should not be used automatically when the stone’s treatment history is unknown.
Fracture-filled, cavity-filled or dyed sapphires require special care and may need to be cleaned only with a damp cloth. Acids and high heat can damage certain filling materials.
Store sapphire away from softer gemstones because its hardness allows it to scratch many other materials.
Repairs and Resetting
Tell the jeweler about all known treatments before resizing, soldering, polishing or resetting sapphire jewelry.
Untreated and heat-treated sapphire can tolerate normal professional repair procedures, but direct heat should still be controlled carefully. Filled or diffusion-treated stones require additional precautions. Recutting a shallow diffusion-treated sapphire may alter or remove part of its color.
What Creates Sapphire Value?
Sapphire value is shaped by several connected factors:
- Strength, attractiveness and uniformity of color
- Transparency and the visibility of inclusions
- Cut quality and face-up brightness
- Carat weight and apparent size
- Natural versus laboratory-grown origin
- Treatment history
- Geographic origin, when reliably determined
- Laboratory documentation
- Rarity within a particular color or category
Size becomes increasingly important when combined with fine color and clarity. Large sapphires exist, but large stones of exceptional quality are much rarer.
An unheated sapphire may command a premium because it possesses desirable color without heat treatment. However, “unheated” does not automatically mean beautiful. A finely colored heated sapphire may be more attractive than a poorly colored unheated stone.
Buying Sapphire with Confidence
Look first for a sapphire whose color appeals to you. Then consider its brightness, transparency, cut, treatment history and documentation.
A famous origin can strengthen the story, but it should support — not replace — the beauty of the gemstone itself.
From the collection
In the collection now
Each stone is listed with its treatment, origin and Otzera 50 rating.
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Distinguished — rated 36 of 50 on the Otzera 501.47 ct Unheated Yogo Sapphire — GIA Origin Report
$9,850.00
-
Distinguished — rated 39 of 50 on the Otzera 504.06 ct Ceylon Blue Sapphire — GIA Origin Report
$8,900.00
-
Distinguished — rated 36 of 50 on the Otzera 504.04 ct Tanzanian Color-Change Sapphire — GIA Origin Report
$6,495.00
-
Distinguished — rated 35 of 50 on the Otzera 502.73 ct Unheated Blue Sapphire — GIA Report
$4,950.00
Questions
Have a question about sapphire?
Treatment, origin, a laboratory report or a particular stone — ask our gemologist. We reply within two business days.












