Turquoise: what it is, how to tell it apart, and how to care for it

Short answer: turquoise is a soft, porous blue-to-green stone coloured by copper. It is beautiful and it is vulnerable - the single most useful thing to know about it is that it absorbs whatever it touches.

What it is

Turquoise is a hydrated phosphate of copper and aluminium. The copper gives the blue; iron pushes it towards green. The dark veining people recognise is the host rock it grew in, called the matrix, and whether matrix is a flaw or a feature is purely a matter of taste - some of the most sought-after material is heavily veined.

How soft it is

It sits around 5 to 6 on the Mohs scale, below quartz and well below sapphire. In practice that means a turquoise ring will pick up marks that an agate or amethyst ring would shrug off. It belongs in a protective setting, and it is better suited to a piece you wear by choice than to one you wear through heavy work.

The porosity problem - and what it means day to day

Turquoise is full of microscopic pores. Skin oils, hand cream, perfume, soap, chlorinated water and sweat all soak in, and over years they shift the colour, usually towards green or brown. This is not damage in the sense of a crack; it is the stone recording your life. Some people like that. If you do not:

  • Put it on last, after perfume and lotion, and take it off first.
  • Keep it out of pools and the sea.
  • Clean with a dry or barely damp soft cloth - never soak it, never use an ultrasonic cleaner.
  • Store it away from direct heat, which dries it and can craze the surface.

Stabilised, treated, reconstituted, imitation

Most turquoise on the market has been treated, and the words matter:

  • Natural - cut and polished, nothing added. Uncommon in good colour.
  • Stabilised - impregnated with clear resin to harden it and hold the colour. Still turquoise, and the great majority of what is sold in jewellery.
  • Reconstituted - turquoise powder bound with resin and pressed. Turquoise in origin, not a single stone.
  • Imitation - dyed howlite, magnesite or plastic. Not turquoise at all.

A seller should tell you which one you are buying. We state what each of our pieces uses rather than leaving it to the word "natural" to do the work.

What it is said to mean

Tradition, not physics - and worth saying so. Turquoise is one of the oldest stones in human use, found in Egyptian, Persian and Anatolian work thousands of years old, and across those cultures it was carried as a guard on journeys. In Turkish the name of the stone and the name of the country share a root through the French turquoise, "Turkish stone", because it reached Europe along trade routes through Anatolia. People wear it for that history as much as for the colour.

Choosing one

Decide first whether you want even colour or strong matrix, because they are different stones to live with. Then ask what treatment it has had. Then look at the setting: with a stone this soft, a bezel that covers the edge is worth more than an extra millimetre of surface.

Pieces from our collection related to this guide