Turquoise
Turquoise is one of the world’s oldest known gemstones—and one of the most interesting materials to learn about. Its colors can range from pale blue and classic “turquoise blue” to blue-green, green, and even yellow-green. Some pieces are nearly solid in color, while others contain dramatic webs, patches, or veins of the surrounding host rock known as matrix.
For lapidaries and collectors, turquoise offers an enormous amount of variety. Two pieces from the same mine can look completely different, while turquoise from mines hundreds or thousands of miles apart can sometimes look remarkably similar.
Getting to Know Turquoise – Learning Series 001 (PDF)
Browse Turquoise Cabochons in the store
More Than Just a Blue Stone
Turquoise is a hydrated copper aluminum phosphate mineral. Copper is primarily responsible for its familiar blue colors, while variations in chemistry and the material surrounding the turquoise can contribute to greens, yellows, matrix patterns, and other differences in appearance.
Turquoise forms in dry regions where mineral-rich groundwater moves through fractures and cavities in rock. Over long periods of time, the right combination of copper, aluminum, phosphorus, water, and geology can create seams, nodules, veins, and other deposits of turquoise.
The American Southwest—particularly Nevada and Arizona—is famous for turquoise, but important deposits are also found in New Mexico, Mexico, China, Iran, and several other parts of the world.
Natural, Stabilized, Treated—and Imitation
One of the most important things to understand about turquoise is that not everything sold as “turquoise” is the same.
Natural turquoise has not been impregnated with resin or otherwise stabilized to strengthen it. It is cut and polished essentially as it came from the ground.
Stabilized turquoise has been treated, usually with resin, to strengthen porous material and make it more suitable for cutting, polishing, and jewelry. Stabilization is common and does not automatically make a piece undesirable. What matters is knowing what you are buying.
Other treatments may alter color or appearance, and some material sold as turquoise is actually dyed stone, reconstructed material, composite material, or a complete imitation.
That is one reason education is so important when buying turquoise.
Can You Identify the Mine by Looking at It?
Sometimes a combination of color, matrix, pattern, and provenance can strongly suggest a particular source. But appearance alone usually cannot prove which mine produced a piece of turquoise.
Certain mines are famous for recognizable looks, but mines can produce many different varieties of material—and similar-looking turquoise can come from entirely different places.
A trustworthy identification therefore depends on more than simply saying, “It looks like Kingman,” “It looks like Royston,” or “It looks like Number 8.” Good provenance matters.
What Makes Turquoise Valuable?
There is no single formula for determining turquoise value. Collectors may consider:
- Color and overall appearance
- Pattern and matrix
- Hardness and ability to take a good polish
- Natural versus stabilized or otherwise treated material
- Rarity and availability
- Mine or geographic provenance
- Quality of the cutting
- Size and shape
- Personal preference
Most importantly, rare does not automatically mean beautiful, and beautiful does not have to mean rare. Buy turquoise you enjoy looking at.
Start Here: Getting to Know Turquoise
If you are new to turquoise—or simply want a refresher—start with our Getting to Know Turquoise Learning Series guide.
It covers the basics of what turquoise is, how it forms, colors and matrix, natural and stabilized material, and some of the terminology you will encounter when buying, collecting, or cutting turquoise.
Getting to Know Turquoise – Learning Series 001 (PDF)
More Turquoise Topics Are Coming
This page will grow as additional Learning Center articles, guides, photographs, and reference materials are added. Future topics may include turquoise mines and geographic regions, natural versus stabilized turquoise, treatments and imitations, buying turquoise, evaluating cabochons, Chinese turquoise, Southwestern turquoise history, and examples of rough material through finished cabochons.
Turquoise is a subject you can study for years and still find something new.
The Little Lapidary
Life’s Too Short To Cut Ugly Rocks! — Used with permission from Highland Park Lapidary