September birthstone
Sapphire
The September birthstone is sapphire. Sapphire is corundum in every color except red, which the trade calls ruby, so pink, yellow, green and colorless sapphires are all correct sapphires. At 9 on the Mohs scale it is exceptionally durable, which is why antique sapphire rings so often survive a century of daily wear with the stone untouched.
- Species
- Corundum, the same mineral as ruby
- Color range
- Blue above all, and also pink, yellow, green, orange and colorless
- Mohs hardness
- 9
- Also this month
- Nothing else on the modern US list
Blue sapphire is the backbone of European antique colored stone jewelry. It appears as the center of Victorian and Edwardian clusters surrounded by old cut diamonds, as calibre cut lines in Art Deco platinum, and as the classic sapphire and diamond three stone ring that has never gone out of production since.
Heat treatment to improve color and clarity is routine in the modern trade and has been used for a very long time. An unheated stone of good color commands a premium, but establishing that a stone is unheated requires laboratory testing, so we say what we know and never more.
Ceylon, Kashmir and Burma are the origin names that carry the highest premiums. Origin cannot be determined by eye, only by laboratory analysis of inclusions and trace elements, so treat any confident origin claim without a report as an opinion rather than a fact.
In antique and vintage jewelry
Cluster rings with an oval or cushion sapphire surrounded by old cut diamonds, calibre cut sapphire lines in Deco platinum, three stone rings, and sapphire and diamond line bracelets.
Wearing and caring for it
About as easy as gemstones get. Warm water, mild soap and a soft brush, and a claw check once a year on a ring worn daily.
As a gift
The safest colored stone to give for daily wear. It survives real life, the blue works with every metal, and antique cluster rings offer far more presence than a modern solitaire at the same price.
Common questions
Are all sapphires blue?
No. Sapphire is corundum in any color other than red. Pink, yellow, green, purple, orange and colorless sapphires all exist, and colorless sapphire was used as a diamond substitute in some period jewelry.
Is a sapphire good for an engagement ring?
Yes, and historically it was the default before diamond marketing took over. At 9 on the Mohs scale it handles daily wear better than almost any other colored stone.
Can you tell where a sapphire came from?
Not by eye. Origin determination requires laboratory analysis, so we only state an origin when there is a report to support it.
Shop the pieces
Shop sapphire jewelry
Antique and vintage pieces set with sapphire, each one a single example.
Nothing matching this is available right now. Every piece is a single example and sells once, so this changes weekly. Browse everything in stock or ask our buyers to look for it.