Two lists, not one

Birthstones by month

The list on this page is American: adopted by the National Association of Jewelers at Kansas City in 1912, and changed three times since, in 1952, 2002 and 2016. It is a trade standard, not a tradition. The table gives the list as it was adopted and as it stands today, and marks the months where they differ.

A hand-coloured plate of two rock fragments studded with dark blood-red dodecahedral garnet crystals, one bedded in grey-green schist and one in rusty brown matrix, with two loose crimson crystals and two outline diagrams of the twelve-sided form.

GarnetJanuary

A hand-coloured plate of two quartz specimens: above, a crust of small violet amethyst points on a pale cream nodule; below, a larger broken mass crowded with faintly purple, sharply pyramidal quartz crystals over its whole upper surface.

AmethystFebruary

A hand-coloured plate of a large broken beryl crystal, its vertical faces finely striated and shading from sea-green through milky white to buff, with a smaller weathered prism beside it and an outline diagram of the six-sided crystal below.

AquamarineMarch

DiamondApril

A hand-coloured engraving of two emerald specimens: a slender deep-green hexagonal prism lying across a pale grey calcite matrix, and below it a large blocky green crystal seated in white rock speckled with small green grains.

EmeraldMay

A single valve of the pearl oyster shown against a black ground inside an ornamental printed border: the shell is creamy white with concentric growth lines and a notched hinge, and one small round pearl sits attached to the nacre near its right edge.

PearlJune

A hand-coloured engraving of nineteen numbered corundum crystals in rows, most of them rose and crimson ruby, barrel-shaped or six-sided; also an orange-brown prism, a pale grey star-stone, and at lower right one large deep blue sapphire crystal.

RubyJuly

A chromolithograph headed Epidote, Garnet and Olivine. Low on the plate a pale yellow-green olivine crystal with a flat terminated top, and at the right the same stone cut as a vivid grass-green oval, among dark red garnets and green epidote.

PeridotAugust

A hand-coloured plate headed Colored Stones. At top left a deep blue cushion-cut sapphire; at top centre a large rough blue-grey sapphire showing a white six-rayed star; below them ruby, amethyst, yellow and orange stones, pale green cabochons and banded agate slices.

SapphireSeptember

A hand-coloured engraving of a single opal nodule set alone on the page: an irregular water-worn lump whose broken face is milky blue-green and cream with faint yellow patches, edged along the underside by a rough dark brown weathered crust.

OpalOctober

A chromolithograph of topaz: a pale blue crystal seated in buff matrix, a tall deep golden-orange striated prism, a lemon-yellow crystal on a druse of white crystals, a small rose-red prism, and cut stones in pale blue, amber, yellow and pink.

TopazNovember

A hand-coloured engraving of three turquoise specimens one above another: a pale blue-green crust broken into rounded patches within a dark green rind, a knobbly botryoidal mass, and a flat splintery slab of clear sky-blue turquoise seen edge-on.

TurquoiseDecember

Month	Today's list	The 1912 list
January	Garnet	Garnet
February	Amethyst	Amethyst
March	Aquamarine, Bloodstone (changed since 1912)	Bloodstone, Aquamarine
April	Diamond	Diamond
May	Emerald	Emerald
June	Pearl, Moonstone, Alexandrite (changed since 1912)	Pearl, Moonstone
July	Ruby	Ruby
August	Peridot, Spinel, Sardonyx (changed since 1912)	Sardonyx, Peridot
September	Sapphire	Sapphire
October	Opal, Tourmaline	Opal, Tourmaline
November	Topaz, Citrine (changed since 1912)	Topaz
December	Turquoise, Zircon, Tanzanite (changed since 1912)	Turquoise, Lapis lazuli

5 of the twelve months have changed since 1912, marked above. The 1912 list is as G. F. Kunz printed it in The Curious Lore of Precious Stones (1913); today's is GIA's.