September 23 – October 22 · Air

Libra birthstones

Libra carries Opal and Peridot in the zodiac tradition.

Opal

Composition Hydrated silica (SiO₂·nH₂O) — 3 to 21 percent water by weight
Hardness · System 5.5–6.5 · Amorphous

The play of colour comes from stacked silica spheres diffracting light — the same physics as a butterfly wing, not pigment.

Traditionally linked to imagination, emotional range and creative flow.

Peridot

Composition Magnesium iron silicate ((Mg,Fe)₂SiO₄) — gem-quality olivine
Hardness · System 6.5–7 · Orthorhombic

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.

Sign or month?

Libra runs September 23 – October 22, which crosses two calendar months — so the zodiac stone and the monthly birthstone may or may not agree depending on your exact date. Neither system overrules the other; the zodiac one is simply older.

Compare against the monthly chart →

← All zodiac birthstones