Sapphire

Natural Faceted Gems

Sapphire is gem-quality corundum in every color except the red classified as ruby. Blue sapphire owes its color chiefly to traces of iron and titanium; other trace elements produce yellow, green, pink, purple, orange, and colorless stones.

Identity

Material or variety: Sapphire
Scientific or material identity: Corundum
Classification: Natural mineral or mineral variety
Composition or formula: Al₂O₃
Crystal system or structure: Trigonal
Geological or manufacturing origin: Can form in more than one geological environment, or combines several materials.
Mohs hardness: 9
Specific gravity: 3.95 to 4.10

Origins

Australia · Madagascar · Myanmar · Sri Lanka · Thailand

Appearance & optical properties

royal blue corundum.

History & discovery

The name comes through Latin and Greek sappheiros, a word that probably once referred to lapis lazuli. Sapphire has adorned royal and clerical dress for centuries; in 1981, Lady Diana Spencer’s blue sapphire engagement ring renewed its modern association with royalty.

Uses & care

Common uses: Sapphire is cut for rings and other jewelry. Star material is made into cabochons, while transparent stones are commonly faceted to show their color and brilliance.
Handling and cleaning: Warm soapy water is always safe. Sapphire is hard, tough, and stable in normal wear, but stones with filled fractures, cavities, or dye should be cleaned only with a damp cloth and kept away from acids.

Jewellery

16 pieces of Sapphire jewellery. Learners earn each one in DigMyGem by learning words; until then it shows as a silhouette.

Stuart Sapphire
Crown
A 104-carat blue sapphire from Sri Lanka set at the front of the Imperial State Crown of the British Crown Jewels. It once belonged to King James II and was worn by later monarchs at their coronations.
Logan Sapphire
Brooch
A 422.98-carat cushion-cut sapphire from Sri Lanka, one of the largest faceted blue sapphires, set in a silver and gold brooch ringed by twenty round diamonds. It was given to the Smithsonian in 1960.
Photo: Chip Clark, Smithsonian staff, Public domain, via Wikimedia Commons
Bismarck Sapphire Necklace
Necklace
A sapphire necklace designed by Cartier in 1935 around a large Burmese sapphire bought by Countess Mona von Bismarck. She donated it to the Smithsonian in 1967.
Photo: Jorfer ( talk · contribs ), Public domain, via Wikimedia Commons
Star of India
Jewel
A 563.35-carat greyish-blue star sapphire from Sri Lanka, almost flawless and unusual for showing a star on both faces. It was stolen from the American Museum of Natural History in 1964 and recovered, and it remains there today.
Star of Bombay
Ring
A 182-carat violet-blue star sapphire from Sri Lanka, first set in a platinum ring and given by Douglas Fairbanks to the actress Mary Pickford. She left it to the Smithsonian, which displays it today.
Photo: James St. John, CC0, via Wikimedia Commons
Diana's Sapphire Ring
Ring
A 12-carat oval Ceylon sapphire surrounded by fourteen diamonds in white gold, made by Garrard and chosen by Prince Charles for Lady Diana Spencer in 1981. It is now worn by Catherine, Princess of Wales.
St Edward's Sapphire
Crown
An octagonal rose-cut blue sapphire set in the top cross of the British Imperial State Crown, it is the oldest gem in the Royal Collection, reputed to have come from a ring worn by Edward the Confessor.
Photo: 'British School' [1], Public domain, via Wikimedia Commons
Queen Marie of Romania Sapphire
Pendant
A 478.68-carat cornflower-blue Ceylon sapphire that Cartier set as the pendant centrepiece of a diamond sautoir, famously worn by Queen Marie of Romania at her 1922 coronation.
Hall Sapphire and Diamond Necklace
Necklace
A Harry Winston necklace of 36 matched cushion-cut Sri Lankan sapphires totalling 195 carats, framed by 435 brilliant-cut diamonds in platinum, now displayed at the Smithsonian.
Photo: Chip Clark, Smithsonian staff, Public domain, via Wikimedia Commons
Black Star of Queensland
Pendant
A 733-carat black star sapphire from Queensland, long the world's largest gem-quality star sapphire, mounted in white gold and ringed by 35 pear-shaped diamonds.
Photo: greyloch, CC BY-SA 2.0, via Wikimedia Commons
Star of Asia
Jewel
A 330-carat blue star sapphire from Sri Lanka, prized for its rich colour and clear six-ray star, held in the Smithsonian National Museum of Natural History.
Star of Adam
Jewel
A blue star sapphire discovered in Ratnapura, Sri Lanka, in 2015 and named for the tradition that Adam lived on nearby Adam's Peak; it is the largest blue star sapphire known.
Ruspoli Sapphire
Jewel
A 136.9-carat blue sapphire whose history was long confused with the Grand Sapphire of Louis XIV; it is now understood to be a distinct historic gem once sold between European jewellers.
James J. Hill Sapphire
Necklace
A 22.66-carat Kashmir sapphire with velvety cornflower colour, bought in 1886 for a diamond-and-sapphire necklace; it later sold at Christie's as the world's most valuable known sapphire.
Star of Artaban
Jewel
A 287-carat milky-blue cabochon star sapphire of obscure origin, believed to come from Sri Lanka and donated to the Smithsonian in the early 1940s.
Star of Pure Land
Jewel
A 3,563-carat purple star sapphire found near Ratnapura, Sri Lanka, and unveiled in 2026 as the largest documented natural purple star sapphire, kept as a loose unmounted stone.