Genuine turquoise impregnated with resin. Legitimate, near-universal, and often undisclosed.
Iran, the American Southwest, China, Egypt, Mexico
Most turquoise as it comes out of the ground is too porous and too chalky to cut, polish or wear. Stabilisation forces clear epoxy or acrylic into the pore structure under pressure, which hardens the stone, deepens and fixes the colour, and stops it discolouring against skin. The great majority of turquoise in commercial jewellery has been through this, and reputable dealers say so.
It is worth understanding what stabilisation is not. It does not add colour — that would be dyeing, which is a separate and much less acceptable treatment often applied at the same time. And it does not create material: the stone is genuine turquoise throughout, unlike reconstituted block, which is powder in resin.
Detecting it without a laboratory is genuinely hard, which is the honest position. A stabilised stone often sounds slightly duller and more plastic when tapped against a tooth or a hard surface, may give a faint polymer note under a briefly heated pin, and tends to a more even, saturated colour than untreated material of the same grade. None of these is conclusive. What is reasonable is to assume stabilisation as the default and to expect a seller claiming untreated natural stone to justify the claim and the price.
These apply to this model and not to the rest of Turquoise. Work them alongside the maker's general checks, not instead of them.
The base rate is the strongest evidence available: most turquoise on the market is stabilised. A claim of untreated natural stone is a claim that should come with a mine name, and a price that reflects it. Treat silence on treatment as an answer.
Untreated turquoise is porous and genuinely changes with wear, absorbing skin oils and darkening or greening over years — a quality many collectors specifically want. Stabilised stone is sealed and stays as it was. A decades-old piece with no colour change at all was probably treated.
Resin-impregnated stone gives a slightly duller, more plastic click against a hard surface than dense untreated turquoise, which rings a little. It is a subtle test that requires having heard both, and it is suggestive rather than conclusive.
Well below natural untreated stone but far above simulant — it is real turquoise, and priced as treated real turquoise.
An orientation for honest, unrestored condition — never an appraisal, and never a quotation.
Lovenhall StoneThe tests tell you what it is. The instrument reads a photograph and offers a name to start from — then hands you back to the tile and the coin, which are what settle it.