September · Deep blue

September birthstone: Sapphire

The stone for September in both the modern and traditional lists.

Modern birthstone Sapphire
Traditional birthstone Sapphire
Colour Deep blue
Birth flower Aster and Morning Glory
Zodiac signs Virgo, Libra
Hardness (Mohs) 9

Kashmir sapphires mined for a few decades from 1881 produced a velvety cornflower blue that has never been matched. They now sell for many times the price of comparable stones from elsewhere.

September stones in detail

Sapphire

Composition Aluminium oxide (Al₂O₃) — corundum coloured by iron and titanium
Hardness · Crystal system 9 · Trigonal
Mined in Sri Lanka, Madagascar, Myanmar, Australia, USA (Montana)

Padparadscha — a pink-orange sapphire named after the lotus flower — is the rarest colour and outprices most blues.

Traditionally associated with judgement, focus and keeping a promise.

Care. Warm soapy water. Safe in ultrasonic unless fracture-filled.

Spotting a fake. Heat treatment is near-universal and disclosed. Untreated sapphire commands a large premium and should come with a lab report — no report, assume treated.

September birth flowers

Aster

Traditionally signifies patience and elegance.

Morning Glory

Traditionally signifies affection that arrives early.

More on September birth flowers →

If you go by zodiac sign instead

September spans two signs — Virgo and Libra — and the zodiac stone list does not match the monthly one. Which applies to you depends on the day, not just the month.

Virgo stones · Libra stones

Questions about the September birthstone

What is the birthstone for September?

Sapphire in the modern list.

What colour is the September birthstone?

Deep blue.

What is the September birth flower?

Aster and Morning Glory — signifying patience and elegance.

Is it hard enough to wear every day?

Sapphire sits at 9 on the Mohs scale. That is hard enough for a ring in daily wear.

Other months

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