The list below includes gemstones borrowed from ‘The Curious Lore of Precious Stones’ by George Frederick Kunz and more closely looks at the connection between earth materials and the season around one’s birth. I’ve bolded the appropriate stones featured in simplified, modern birthstone calendars.

JANUARYGarnet, Sapphire
FEBRUARY – Amethyst, Sapphire, Pearl
MARCH – Bloodstone, Jasper, Aquamarine
APRIL – Diamond, Sapphire, Pearl
MAY – Agate, Emerald, Chalcedony, Carnelian
JUNE – Agate, Pearl, Moonstone, Turquoise, Alexandrite
JULY – Ruby, Carnelian, Onyx, Sardonyx, Turquoise
AUGUST – Carnelian, Moonstone, Peridot, Topaz, Alexandrite
SEPTEMBER – Blue Sapphire, Lapis Lazuli, Coral
OCTOBER – Opal, Aquamarine, Beryl
NOVEMBER – Topaz, Citrine, Pearl
DECEMBER – Turquoise, Ruby, Bloodstone

1st – Rose Beryl, Paper
2nd – Crystal, Cotton
3rd – Chrysophrase, Leather
4th – Moonstone, Silk
5th – Carnelian, Wood
6th – Peridot, Sugar
7th – Coral, Wool
8th – Opal, Clay
9th – Citrine, Willow
10th – Turquoise, Tin
11th – Garnet
12th – Amethyst, Linen
13th – Agate
14th – Ivory, Lace
15th – Topaz
20th – China
25th – Silver
30th – Pearl
35th – Jade
40th – Ruby
45th – Sapphire
50th – Gold
55th – Emerald
60th – Diamond