Capricorn Birthstone: Garnet and Ruby and What They Mean

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 travelers as a stone of safe return, and long associated with vitality and steady energy.

Ruby

Composition Aluminum oxide (Al₂O₃) — corundum colored by chromium

Hardness · System 9 · Trigonal

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

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

Cover of The 2027 Sky Calendar, a free PDF from AstroHot

18 pages · printable

The 2027 Sky Calendar — free PDF

Every retrograde, eclipse, new and full moon of 2027 to the minute, already converted to your city. A month to a page, ready to print.

The reasoning

Why Capricorn gets Garnet and Ruby

Capricorn is ruled by Saturn and begins at the winter solstice, the darkest point of the year, and both of its stones are deep reds that glow with very little light. Garnet, the January stone, was carried as a lamp in legend — Noah was said to have hung one in the ark — and it stands for steady energy over the long haul, which is how Capricorn works. Ruby adds ambition and decisive action. The pair suits a sign that climbs slowly and does not stop.

Other stones often given to Capricorn

Onyx Smoky Quartz Hematite

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 monthly chart →

January supplies 19 of the sign’s days and December just 10, which tips the monthly chart toward Garnet, the January stone. December is also lighter in births than its days imply: 33.9% of the sign’s US births in 2000–2014, from 34.5% of its days.

In the monthly chart, Garnet is January’s modern birthstone; Ruby is July’s modern birthstone. Only one of those months falls inside Capricorn.

December Turquoise, Zircon, Tanzanite January Garnet

The stones themselves

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

Garnet (6.5–7.5) suits an everyday ring if you watch for chipped facet edges on the softer species; so does Ruby (9), where the thing to watch is glass filling — ask whether the stone is treated. What the scale means →

Capricorn birthstones on the Mohs hardness scale

Capricorn’s zodiac stones: Garnet 6.5–7.5, Ruby 9. The December and January month stones it also covers: Turquoise 5–6, Zircon 6–7.5, Tanzanite 6–7. Ruby stays at 7 or harder across its whole range, so dust cannot scratch it.

Cite this page

AstroHot. “Capricorn Birthstone: Garnet and Ruby and What They Mean.” Accessed October 27, 2026. https://astrohot.com/birthstones/by-zodiac/capricorn/

For Wikipedia

{{cite web |title=Capricorn Birthstone: Garnet and Ruby and What They Mean |url=https://astrohot.com/birthstones/by-zodiac/capricorn/ |website=AstroHot |access-date=2026-10-27}}