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Crystals

Birthstones by Month: The Modern List and Where It Came From

Twelve months, nineteen gems. The list jewelers use today, and how it grew from a priest's breastplate to a 2016 update.

By Star Gem Daily editorial teamUpdated Facts last checked
What changed
  • : First published.

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On this page
  1. The modern birthstone list
  2. Month by month
  3. Where the list came from
  4. Choosing and caring for a birthstone

The modern birthstone list

This is the list most jewelers in the United States use, as published by GIA. Hardness is on the Mohs scale, where higher numbers scratch less easily.

Month Birthstone(s) Mohs hardness Wear notes
January Garnet 6.5 to 7.5 Good for everyday jewelry
February Amethyst 7 Can fade with long strong light
March Aquamarine, bloodstone 7.5 to 8; about 6.5 to 7 Both durable
April Diamond 10 Hard, but a sharp knock can chip it
May Emerald 7.5 to 8 Often has inclusions; avoid ultrasonic cleaners
June Pearl, moonstone, alexandrite 2.5 to 3; 6 to 6.5; 8.5 Pearl is very soft
July Ruby 9 Very durable
August Peridot, spinel, sardonyx 6.5 to 7; 8; about 6.5 to 7 Spinel added in 2016
September Sapphire 9 Very durable
October Opal, tourmaline 5 to 6.5; 7 to 7.5 Opal dislikes heat and knocks
November Topaz, citrine 8; 7 Both good for daily wear
December Turquoise, tanzanite, zircon 5 to 6; 6 to 7; 6 to 7.5 Turquoise is porous

Hardness values are from GIA's gem encyclopedia except bloodstone and sardonyx, which are chalcedony varieties (about 6.5 to 7).

Month by month

January: garnet. Garnet is not one mineral but a group, and GIA notes it comes in almost every color, though deep red is the classic. It has been found in jewelry from ancient Egypt and Rome.

February: amethyst. Purple quartz. The Greek name means "not drunk", from an old belief that it prevented intoxication.

March: aquamarine and bloodstone. Aquamarine is the sea-blue form of beryl, the same mineral as emerald. Bloodstone is dark green chalcedony with red spots.

April: diamond. Crystallized carbon and the hardest natural material. Hardness only measures scratch resistance; diamonds can still chip along their cleavage planes.

May: emerald. Green beryl, usually with visible inclusions that the trade calls jardin, French for "garden". Most emeralds are treated with oil or resin to improve clarity, so heat, steam and ultrasonic cleaners are risky.

June: pearl, moonstone and alexandrite. Pearl is organic and soft. Moonstone is a feldspar with a soft glow. Alexandrite, added in 1952, is a rare color-change chrysoberyl that looks green in daylight and red under incandescent light.

July: ruby. Red corundum, colored by chromium. Rubies and sapphires are the same mineral; only red corundum is called ruby.

August: peridot, spinel and sardonyx. Peridot is gem olivine. Spinel, added in 2016, comes in reds, pinks and blues and was mistaken for ruby for centuries. Sardonyx is banded chalcedony with reddish layers.

September: sapphire. Corundum in every color except red. Blue is classic, but pink, yellow and green sapphires are common.

October: opal and tourmaline. Opal holds water in its structure and shows play of color. Tourmaline, added in 1952 (pink tourmaline originally), comes in more colors than almost any other gem.

November: topaz and citrine. Topaz is hard and comes in many colors; most blue topaz is treated. Citrine, added in 1952, is yellow to orange quartz.

December: turquoise, tanzanite and zircon. Turquoise is an opaque blue-green copper mineral. Zircon was added in 1952 and tanzanite, a blue-violet zoisite found only in Tanzania, in 2002.

Where the list came from

The idea of twelve special stones is old. The Book of Exodus describes a breastplate worn by Aaron, the high priest, set with twelve stones for the twelve tribes of Israel. In the first century, the historian Josephus linked those stones to the twelve months and the twelve signs of the zodiac, and in the fifth century St. Jerome encouraged Christians to use them. Ancient stone names do not always match modern minerals, so scholars still debate which gems were on the breastplate.

Wearing a single stone for your birth month is newer. The International Gem Society traces it to the 16th century in Germany or Poland. In 1912 the National Association of Jewelers in the United States (now Jewelers of America) published a standard list. It was revised in 1952, which added alexandrite, citrine, pink tourmaline and zircon; tanzanite was added in 2002 and spinel in 2016.

Other countries and traditions have their own lists, and so do zodiac-based systems. See zodiac stones for those.

Choosing and caring for a birthstone

If you plan to wear a birthstone every day, hardness and toughness matter. Rings take the most knocks. Pearl, opal, turquoise and tanzanite are better suited to earrings, pendants or careful wear. Harder stones like sapphire, ruby, topaz and spinel are better for rings. A small birthstone reference book is a nice gift alongside a stone, and our crystal care guide covers cleaning. Want a quick answer for a date? Try the birthstone finder.

Common questions

What is the birthstone for November?

Topaz and citrine. Citrine was added in 1952, alongside the older topaz.

Why do some months have three birthstones?

Jewelers added alternatives over the years, usually to offer a more affordable or more durable choice. June has pearl, moonstone and alexandrite; August has peridot, spinel and sardonyx; December has turquoise, tanzanite and zircon.

Is zircon the same as cubic zirconia?

No. Zircon is a natural mineral. Cubic zirconia is a man-made material often used to imitate diamond.

Sources

  1. GIA, Birthstones for Each Month
  2. GIA, March Birthstones: Aquamarine and Bloodstone
  3. GIA, June Birthstones: Pearl, Alexandrite and Moonstone
  4. GIA, August Birthstones: Peridot, Spinel and Sardonyx
  5. GIA, October Birthstones: Opal and Tourmaline
  6. GIA, November Birthstones: Topaz and Citrine
  7. GIA, December Birthstones: Tanzanite, Turquoise and Zircon
  8. International Gem Society, History of Birthstones
  9. National Jeweler, Rocks On: The Evolution of the Birthstone List

Checked Nov 11, 2026. Spot an error? Tell us.

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