Birthstones

Sapphire, September's stone, is worn in crystal practice for wisdom, truth and faithfulness. How to wear and clear it, and why bishops chose it.

October has two birthstones: opal, worn in crystal practice for feeling and making, and tourmaline, chosen by colour for love or balance.

November's citrine is kept for optimism and abundance, golden topaz for confidence. How to wear them, and a short line to say over the stone.

In crystal practice emerald, May's birthstone, is a stone of love and loyalty. Wear it through the engagement; give it when the first year ends.

In crystal practice March's bloodstone is a protective stone of courage, and aquamarine is kept for calm, at the throat. How to wear both.

In crystal practice June's pearl is kept for calm, moonstone for intuition and alexandrite for change. How to choose between them and wear each.

Ruby, July's birthstone, is a stone of courage, passion and devotion in crystal practice, placed at the heart or the root.

In crystal practice garnet, January's birthstone, is worn low for steadiness in the dark months, carried for travel and given for constancy.

Amethyst, whose Greek name means not drunken, is February's stone, worn in crystal practice for moderation and cleared with smoke or sound.

In crystal practice December's turquoise is a protective stone, best received as a gift. How to wear it, and where tanzanite and zircon fit.

August's three birthstones: peridot for letting go, sardonyx for a partnership that has lasted, and spinel for taking something up again.

Diamond, April's birthstone, stands for clarity, strength and commitment in crystal practice. Wear it for a vow; give it on the eve of a start.

American jewellers voted the modern list at Kansas City in 1912. How the twelve-stone calendar was made, how it changed, and the dates we give.