August · Yellow-green

August birthstone: Peridot

August carries 2 official stones — Peridot, Spinel.

Modern birthstone Peridot, Spinel
Traditional birthstone Sardonyx
Colour Yellow-green
Birth flower Gladiolus and Poppy
Zodiac signs Leo, Virgo
Hardness (Mohs) 6.5–7

Spinel was added in 2016, the most recent change to the modern list. Sardonyx held August in the older tradition and peridot arrived in 1912.

Note the split: Peridot is the modern choice, while Sardonyx held the month in the older list. Both are still considered correct, so if you were told a different stone growing up, that is probably why.

August stones in detail

Peridot

Composition Magnesium iron silicate ((Mg,Fe)₂SiO₄) — gem-quality olivine
Hardness · Crystal system 6.5–7 · Orthorhombic
Mined in Pakistan, Myanmar, USA (Arizona), China, Egypt

Peridot arrives on Earth in meteorites — pallasite meteorites carry gem-quality crystals formed beyond this planet.

Traditionally linked to lightness, release of resentment and fresh perspective.

Care. Soapy water only. Sensitive to acid and rapid temperature change, so no steam and no ultrasonic.

Spotting a fake. Green glass is the common fake. Peridot has unusually strong double refraction — look through it at a straight line and the line appears doubled.

Spinel

Composition Magnesium aluminium oxide (MgAl₂O₄)
Hardness · Crystal system 8 · Cubic
Mined in Myanmar, Tanzania, Sri Lanka, Vietnam, Tajikistan

Several famous "rubies" in the British Crown Jewels — including the Black Prince's Ruby — are spinel.

Traditionally associated with renewal and recovering energy after depletion.

Care. Warm soapy water. Durable and safe in ultrasonic.

Spotting a fake. Historically confused with ruby, and several crown rubies turned out to be spinel. Spinel is singly refractive and ruby is not, which settles it under a loupe.

Sardonyx

Composition Banded chalcedony — alternating layers of sard and onyx
Hardness · Crystal system 6.5–7 · Trigonal
Mined in India, Brazil, Germany, Czech Republic

Its parallel banding made it the preferred material for cameos — carvers cut through a pale layer to reveal a dark one beneath.

Traditionally linked to steadiness, discipline and durable commitments.

Care. Warm soapy water and a soft cloth. Avoid prolonged soaking.

Spotting a fake. Banded agate is often dyed to imitate sardonyx. Natural banding is irregular; dyed banding is too even and the colour sits in the porous layers.

August birth flowers

Gladiolus

Traditionally signifies strength of character.

Poppy

Traditionally signifies remembrance and rest.

More on August birth flowers →

If you go by zodiac sign instead

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

Leo stones · Virgo stones

Questions about the August birthstone

What is the birthstone for August?

Peridot, Spinel in the modern list. The traditional stone is Sardonyx.

What colour is the August birthstone?

Yellow-green.

What is the August birth flower?

Gladiolus and Poppy — signifying strength of character.

Is it hard enough to wear every day?

Peridot sits at 6.5–7 on the Mohs scale. Too soft for a ring worn daily — better in a pendant or earrings.

Other months

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