Birthstone is a gift of a precious material (jewelry, mainly gemstones themselves traditionally associated with various qualities) that symbolizes the month of birth in the Gregorian calendar. It is sometimes also called birthday stone.

Traditional birthstones
Often combined with modern birthstone lists, traditional birthstones are older society-based birthstones. Since many different cultures had their own list, jewelers' lists are often inconsistent over what constitutes a traditional birthstone. The table below contains many stones which are popular choices.

The Gregorian calendar has poems matching each month with its birthstone. These are traditionally the stones in English-speaking societies. It is not known whether these verses below are of the originally Gregorian calendar or not but the poem below was published by Tiffany and Co in 1870.

Three of the verses are repeats,

By her who in January was born No gem save garnets shall be worn They will ensure her constancy True friendship and fidelity. The February born shall find Sincerity and peace of mind, Freedom from passion and from care, If they, the amethyst will wear. By her who in March was born No gem save bloodstone shall be worn They will ensure her constancy True friendship and fidelity. She who from April dates her years, diamonds shall wear, lest bitter tears For vain repentance flow. Who first beholds the light of day In spring's sweet, flower month of May And wears an emerald all her life Shall be a loved and a loving wife. By her who in June was born No gem save pearls shall be worn They will ensure her constancy True friendship and fidelity.

The gleaming ruby should adorn, All those who in July are born, For thus they'll be exempt and free, From lover's doubts and anxiety. Wear a peridot or for thee, No conjugal fidelity, The August born without this stone, `Tis said, must live unloved; alone. A maiden born when autumn leaves Are rustling in September's breeze, A sapphire on her brow should bind; To bring her joy and peace of mind. October's child is born for woe, And life's vicissitudes must know, But lay an opal on her breast, And hope will lull those woes to rest. Who first comes to this world below In dreary November's fog and snow, Should prize the topaz amber hue, Emblem of friends and lovers true. If cold December gave you birth The month of snow and ice and mirth Place on your hand a turquoise blue; Success will bless whate'er you do.

—Gregorian Birthstone Poems

Modern birthstones
In 1912, in an effort to standardize them, the American national association of jewelers, Jewelers of America, officially adopted a list, shown in the "Modern" column in the table below. It is currently the most widely used list in the United States and many other locations, including Australia and Thailand.

Mystical birthstones
Mystical Birthstones are of Tibetan origin and date back over a thousand years.

Ayurvedic birthstones
The Ayurvedic birthstone list is from the ancient Indian medicine and philosophy dating back to ancient India (1500 BC).

By culture of times

Month	Traditional Birthstone(s)	Modern Birthstone(s)	Mystical Birthstone	Ayurvedic Birthstone
January	garnet	garnet	emerald	garnet
February	amethyst	amethyst	bloodstone	amethyst
March	bloodstone, jasper	aquamarine	jade	bloodstone
April	diamond, sapphire	diamond	opal	diamond
May	emerald, agate	emerald	sapphire	agate
June	alexandrite, emerald	moonstone, pearl	moonstone	pearl
July	ruby, onyx	ruby	ruby	ruby
August	sardonyx, carnelian	peridot	diamond	sapphire
September	sapphire, peridot	sapphire	agate	moonstone
October	tourmaline, aquamarine	opal, tourmaline	jasper	opal
November	citrine, topaz	topaz, citrine	pearl	topaz
December	zircon, ruby	turquoise, blue topaz	onyx	ruby

List of birthstones by signs of zodiac
Early civilizations such as India and Babylon have attributed gemstones with magical properties. Over time, astrologers assigned gems of certain colors to the twelve signs of the zodiac to help people influence the planets in their favor.

Sign	Dates	Stone
Aquarius	January 21 - February 19	Garnet
Pisces	February 20 - March 20	Amethyst
Aries	March 21 - April 20	Bloodstone
Taurus	April 21 - May 20	Sapphire
Gemini	May 21 - June 21	Agate
Cancer	June 22 - July 22	Emerald
Leo	July 23 - August 23	Onyx
Virgo	August 24 - September 23	Carnelian
Libra	September 24 - October 23	Peridot
Scorpio	October 24 - November 22	Beryl
Sagittarius	November 23 - December 21	Topaz
Capricorn	December 22 - January 20	Ruby

Anniversary Gemstones

1st Anniversary	Gold Jewelry
2nd Anniversary	Garnet
3rd Anniversary	Cultured or Natural Pearls
4th Anniversary	Blue Topaz
5th Anniversary	Sapphire
6th Anniversary	Amethyst
7th Anniversary	Onyx
8th Anniversary	Tourmaline
9th Anniversary	Lapis Lazuli
10th Anniversary	Diamond Jewelry
11th Anniversary	Turquoise
12th Anniversary	Jade
13th Anniversary	Citrine
14th Anniversary	Opal
15th Anniversary	Ruby
16th Anniversary	Peridot
17th Anniversary	Watches
18th Anniversary	Cat’s Eye
19th Anniversary	Aquamarine
20th Anniversary	Emerald
21st Anniversary	Iolite
22nd Anniversary	Spinel
23rd Anniversary	Imperial Topaz
24th Anniversary	Tanzanite
25th Anniversary	Silver Jubilee
30th Anniversary	Cultured/Natural Pearl Jubilee
35th Anniversary	Emerald
40th Anniversary	Ruby
45th Anniversary	Sapphire
50th Anniversary	Golden Jubilee
55th Anniversary	Alexandrite
60th Anniversary	Diamond