Reference
Birthstones by month
The modern list was fixed by the American jewelers' association in 1912 and has gained a few alternates since. Each month below gives the traditional stone, how hard it wears, what a fine 1 carat example costs at today's rates, and the sensible substitute when the classic is priced out of reach.
Anniversary gemstones by year
The traditional list, with the classic stone priced where we model it.
| Year | Traditional | A fine 1 ct today |
|---|
On hardness
The Mohs number is how well a stone resists scratching, and it decides whether it survives a ring. Diamond (10), sapphire and ruby (9) and alexandrite (8.5) are everyday-ring stones. Emerald (7.5–8) is hard but brittle, and is usually oiled to hide fractures. Below 7 — opal, pearl, turquoise — the stone belongs in earrings or a pendant, not on a hand.