December · Blue to blue-violet

December birthstone: Turquoise

December carries 3 official stones — Turquoise, Zircon, Tanzanite.

Modern birthstone Turquoise, Zircon, Tanzanite
Traditional birthstone Turquoise
Colour Blue to blue-violet
Birth flower Narcissus and Holly
Zodiac signs Sagittarius, Capricorn
Hardness (Mohs) 5–6

Tanzanite joined in 2002 — the first addition to the list in almost a century, and the only birthstone found in one place on Earth.

December stones in detail

Turquoise

Composition Hydrated copper aluminium phosphate (CuAl₆(PO₄)₄(OH)₈·4H₂O)
Hardness · Crystal system 5–6 · Triclinic
Mined in Iran, USA (Arizona, Nevada), China, Egypt

Porous enough to absorb oils and change colour over years of wear — some cultures read that shift as meaningful.

Traditionally the classic travel-protection stone, also linked to plain speech.

Care. Wipe with a dry or barely damp cloth. Never soak, never ultrasonic — turquoise is porous and absorbs whatever it touches.

Spotting a fake. Most affordable turquoise is resin-stabilised, which is normal. Dyed howlite is the outright fake: scratch an inconspicuous spot and dyed material shows white beneath.

Zircon

Composition Zirconium silicate (ZrSiO₄)
Hardness · Crystal system 6–7.5 · Tetragonal
Mined in Cambodia, Myanmar, Sri Lanka, Australia, Tanzania

Not to be confused with cubic zirconia, a synthetic diamond simulant. Natural zircon has high dispersion and real geological age.

Traditionally associated with grounding and restful sleep.

Care. Warm soapy water. Avoid ultrasonic — zircon is brittle and chips at facet edges.

Spotting a fake. Not to be confused with cubic zirconia, which is synthetic and unrelated. Natural zircon shows strong doubling of the back facets viewed through the table.

Tanzanite

Composition Calcium aluminium silicate (Ca₂Al₃(SiO₄)₃(OH)) — blue zoisite
Hardness · Crystal system 6–7 · Orthorhombic
Mined in Tanzania (Merelani Hills — the only source on Earth)

Mined in a strip of land roughly seven kilometres long. At current rates the deposit is expected to run out within decades.

Traditionally linked to perspective shifts and seeing a situation from above.

Care. Warm soapy water and a soft brush. No ultrasonic, no steam — tanzanite is sensitive to sudden temperature change.

Spotting a fake. Effectively all tanzanite is heat-treated to produce the blue; unheated material is brown and rare. Coated imitations exist and need a lab to separate.

December birth flowers

Narcissus

Traditionally signifies the wish for others to stay as they are.

Holly

Traditionally signifies defence and domestic happiness.

More on December birth flowers →

If you go by zodiac sign instead

December spans two signs — Sagittarius and Capricorn — and the zodiac stone list does not match the monthly one. Which applies to you depends on the day, not just the month.

Sagittarius stones · Capricorn stones

Questions about the December birthstone

What is the birthstone for December?

Turquoise, Zircon, Tanzanite in the modern list.

What colour is the December birthstone?

Blue to blue-violet.

What is the December birth flower?

Narcissus and Holly — signifying the wish for others to stay as they are.

Is it hard enough to wear every day?

Turquoise sits at 5–6 on the Mohs scale. Too soft for a ring worn daily — better in a pendant or earrings.

Other months

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