The first century Jewish historian Josephus proclaimed a connection between the twelve stones in Aaron's breastplate, the twelve months of the year, and the twelve signs of the zodiac.
In the eighth and ninth centuries, religious treaties were written associating a particular stone with an apostle. It became common practice to keep twelve stones and wear one a month.
By her who in this month (January) is born
No gem save garnets should 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 an amethyst will wear.
Who in this world of ours their eyes
In March first open shall be wise,
In days of peril firm and brave,
And wear a bloodstone to their grave.
She who from April dates her years,
Diamonds shall wear, lest bitter tears
For vain repentance flow; this stone,
Emblem of innocence, is known.
Who first beholds the light of day
In spring's sweet flowery month of May
And wears an emerald all her life
Shall be a loved and happy wife.
Who comes with summer to this earth,
And owes to June her hour of birth,
With ring of agate on her hand
Can health, wealth, and long life command.
The glowing ruby shall adorn,
Those who in July are born;
Then they'll be exempt and free
From love's doubts and anxiety.
Wear a sardonyx or for thee,
No conjugal felicity;
The August-born without this stone,
`Tis said, must live unloved and lone.
A maiden born when September leaves
Are rustling in September's breeze,
A sapphire on her brow should bind
`Twill cure diseases of the 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
With drear November's fog and snow,
Should prize the topaz's 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.