Ursa – Tanzanite and CZ

Cubic zirconia (CZ) is a lab-created material made of zirconium dioxide, not carbon, and is widely used as an affordable diamond look-alike. It is man-made and can be produced in almost any colour.

Hardness

8–9 (Mohs), usually given as about 8.5

Everyday wear

Cubic zirconia is softer than diamond, so with daily wear it can gradually pick up scratches and lose some sparkle; it may need re-polishing or replacing over time.

Care

Soak briefly in warm water with a few drops of mild dish soap, brush gently with a soft brush, rinse and dry with a lint-free cloth. Store it apart from other jewellery and avoid harsh chemicals, toothpaste and chlorinated water.

Tanzanite is the violet-blue to blue-violet variety of the mineral zoisite. It is mined commercially in only one place, the Merelani Hills of Tanzania, which gives the gem its name.

Birthstone

December

Hardness

6–7 (Mohs)

Everyday wear

Tanzanite has fair to poor toughness and can split if knocked, so it is best in earrings and pendants or worn with care in rings.

Care

Clean with warm, soapy water only; ultrasonic and steam cleaners are never recommended. Avoid sudden temperature changes and high heat.

Meaning and tradition

Tanzanite was only discovered in 1967 and is the gem for 24th wedding anniversaries. In modern crystal lore, many people associate it with intuition, spiritual awareness and a calm, soothing presence.