Colors
- Pale blue to intense ultramarine with violet undertones
- Shows different colors from different angles
Browse other gems by color: Blue · Purple
Where Tanzanite comes from
- Tanzania only (a few square miles near Mount Kilimanjaro)
Tanzanite meaning and history
The name: Named after Tanzania, its only source.
Meanings and powers attributed to gems are history and folklore. We report them; we do not claim a stone can do anything.
How hard is Tanzanite?
Tanzanite is 6 to 7 on the Mohs scale, where talc is 1, quartz 7 and diamond 10. Toughness, its resistance to chipping and breaking: fair to poor. It has cleavage and can break if struck.
See every birthstone on the hardness chart
How to clean and care for Tanzanite
| Warm soapy water | Safe |
|---|---|
| Ultrasonic cleaner | Never |
| Steam cleaner | Never |
Heat, light and chemicals: Stable in normal wear; avoid very high heat and sudden temperature changes; attacked by hydrochloric and hydrofluoric acid.
Treatments to ask about
Routinely heat treated to turn brownish crystals blue or violet; this is stable.
Can you wear Tanzanite every day?
Wear with care Can chip, crack or scratch. Protective settings, pendants and earrings are safer than everyday rings. Check other stones.
Compare Tanzanite
Turquoise vs Tanzanite · Tanzanite vs Zircon · Tanzanite vs Sapphire · Amethyst vs Tanzanite
Frequently asked questions
What is Tanzanite?
The blue violet variety of the mineral zoisite, found only in Tanzania near Mount Kilimanjaro. It was discovered in 1967.
What month is Tanzanite the birthstone for?
December. It shares the month with Turquoise and Zircon.
How hard is Tanzanite?
6 to 7 on the Mohs scale. Toughness: fair to poor. It has cleavage and can break if struck.
How do you clean Tanzanite?
Warm soapy water: safe. Ultrasonic cleaner: never. Steam: never.
Sources
- GIA: Tanzanite care and cleaning (hardness, toughness, stability, cleaning, treatments)
- AGS: Tanzanite (what it is, colors, sources, history)
- American Gem Society: Birthstones (birthstone months)
Checked October 16, 2026.