Weathered turquoise is often crushed and used to make "composite" or "reconstituted" turquoise described in the "Natural Turquoise and Turquoise Treatments" section below
Turquoise has a hardness of 5 to 6 on the Mohs scale of mineral hardness. This means it is relatively soft compared to many other gemstones. Turquoise can be scratched by harder materials, such as quartz or corundum, so it requires careful handling and protection from abrasion. Turquoise is known for its unique blue and green colors. The color can vary from sky blue to greenish-blue or even green. The presence of Copper impurities in the turquoise gives it the blue color, while iron or Zinc impurities can influence the shade towards green.
The density of turquoise ranges from 2.60 to 2.90 grams per cubic centimeter (g/cm³). This density can help differentiate turquoise from imitations or simulants that may have different weight-to-volume ratios. Turquoise has a pale blue to greenish-blue streak, which is the color left when the Stone is rubbed against a rough surface. The streak color can help distinguish turquoise from similar-looking materials. Turquoise exhibits a conchoidal fracture, which means it breaks with smooth, curved surfaces resembling the interior of a seashell. This fracture is typical of many Minerals and can be observed when turquoise is fractured or chipped.
The physical properties of turquoise are valuable for its identification. They are also valuable information for the care of turquoise jewelry. Important properties are summarized in the accompanying table. Weathering can significantly alter the physical properties of turquoise. Weathered turquoise might still have a desirable color, but its hardness and durability are reduced. This turquoise cannot be cut into useful cabochons or beads. Weathered turquoise is often crushed and used to make "composite" or "reconstituted" turquoise described in the "Natural Turquoise and Turquoise Treatments" section below.
Turquoise has a waxy to sub-vitreous luster, which means it can exhibit a somewhat dull or soft sheen when polished. However, with proper cutting and polishing, turquoise can develop a beautiful and attractive luster. Turquoise is typically opaque, which means it does not allow light to pass through it. In some cases, especially when the stone is thinner or polished into thin cabochons, a small degree of translucency may be observed. Turquoise has poor to distinct cleavage. Cleavage is the tendency of a mineral to break along specific planes or directions. In the case of turquoise, it can show cleavage in one direction, which means it may break or fracture more easily along that direction.
Turquoise typically has a smooth and polished texture when cut and finished as a gemstone. The surface can range from a soft, waxy feel to a slightly glossy or sub-vitreous sheen. The texture can enhance the stone's visual appeal and contribute to its tactile experience. Turquoise has a waxy to sub-vitreous lustre. When properly cut and polished, it can develop a soft and gentle lustre that adds to its beauty. The lustre may vary depending on the quality of the stone and the level of polishing it has undergone. Turquoise is generally opaque, meaning it does not allow light to pass through it. However, some thinner or well-polished turquoise cabochons may exhibit a slight degree of translucency, allowing diffuse light to pass through the stone.
Turquoise is commonly cut into various shapes, with cabochons being the most popular. Cabochons are polished, convex-shaped Gems without facets. The smooth, rounded surface of cabochon-cut turquoise allows the color and matrix patterns to be prominently displayed. Turquoise can also be carved into beads, pendants, or other decorative shapes, highlighting its unique appearance. Turquoise is available in a wide range of sizes, from small beads to large cabochons or even carved sculptures. The size of turquoise Stones can influence their use in Jewelry and their overall visual impact.
Turquoise is known for its distinct blue and green hues. The color can range from sky blue to shades of greenish-blue or even green. The intensity and saturation of the color can vary, with some stones displaying a rich, deep blue, while others exhibit a lighter, more pastel-like shade. The color is influenced by the presence of copper and iron impurities within the stone. Many turquoise stones feature a characteristic matrix pattern. The matrix refers to the veins or web-like patterns of the surrounding host Rock material that becomes part of the turquoise deposit. The matrix can vary in color, texture, and composition, creating unique patterns within the stone. Common matrix colors include brown, black, tan, or golden hues, and they can add depth and character to the overall appearance of turquoise.
