December 22 – January 19 · Earth

Capricorn birthstones

Capricorn carries Garnet and Ruby in the zodiac tradition.

Garnet

Composition Group of silicate minerals — almandine, pyrope, spessartine and others
Hardness · System 6.5–7.5 · Cubic

Garnet is not one mineral but a family. Almandine gives the familiar deep red; tsavorite garnet is green and rarer than emerald.

Traditionally carried by travellers as a stone of safe return, and long associated with vitality and steady energy.

Ruby

Composition Aluminium oxide (Al₂O₃) — corundum coloured by chromium
Hardness · System 9 · Trigonal

Ruby and sapphire are the same mineral. Red corundum is ruby; every other colour is sapphire.

Traditionally associated with courage, appetite for life and decisive action.

Sign or month?

Capricorn runs December 22 – January 19, 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

Two systems, one birth date

Capricorn spans 2 calendar months, so you have more than one birthstone

Zodiac stones Garnet, Ruby
Months it covers December and January
Stones of those months Turquoise, Zircon, Tanzanite, Garnet
In both systems Garnet

December 22 – January 19 — so the sign opens in one month and closes in another. Why the two lists never line up →

The split is uneven: 10 days fall in December and 19 in January. So most people with this sign — 66% — are sold the January stone.

Both stones — Garnet and Ruby — also sit in the monthly list somewhere, which is the usual case.

December Turquoise, Zircon, Tanzanite January Garnet

The stones themselves

Stone Mohs Crystal system Main sources
Garnet 6.5–7.5 Cubic India, Brazil, Madagascar
Ruby 9 Trigonal Myanmar, Mozambique, Thailand

Garnet is the softer at 6.5–7.5 on the Mohs scale — below 7, which means household dust scratches it, so it belongs in earrings or a pendant rather than an everyday ring. What the scale means →

Garnet

Group of silicate minerals — almandine, pyrope, spessartine and others Used since the Bronze Age; Egyptian garnet inlays date to roughly 3100 BCE

Ruby

Aluminium oxide (Al₂O₃) — corundum coloured by chromium Traded along the Silk Road from Burma; Sanskrit called it ratnaraj, "king of gems"