Turquoise physical properties
Turquoise is a unique and historically significant gemstone known for its striking blue color. Here are some of its physical properties: Crystal System: Turquoise typically forms in the triclinic system, but it is mostly cryptocrystalline, with microcrystals visible only under a microscope. Fracture: The fracture pattern is usually shell-like or granular, depending on the development of the pore system within the stone. Hardness: Turquoise has a hardness of 5 to 6 on the Mohs scale, which makes it relatively soft and susceptible to damage if not handled carefully. Toughness: The toughness varies. Some specimens, like the "white scorpion" type, are fragile and prone to breaking, while denser varieties show better durability. Streak: The streak of turquoise is white or green, which can help in identification. Specific Gravity: Its specific gravity ranges from 2.4 to 1.9, though this value may vary slightly depending on the composition. Transparency: Turquoise is generally opaque, though some rare varieties may be translucent. Luster: When polished, it exhibits a waxy to glassy luster, while the fracture surface appears duller. Inclusions: Common inclusions include black spots, dark lines, or brownish iron oxide particles that often form as inclusions within the stone. Refractive Index: The refractive index values are Nα = 1.65, Nβ = 1.62, and Nγ = 1.61. Due to its typical green appearance, most gemologists only record an average of around 1.62. Birefringence: Turquoise has a strong birefringence (DR = 0.040), but this property is rarely observable during standard gemological testing due to its opacity. Optical Properties: It is a biaxial crystal with positive optic sign, and the angle between the two optic axes (2Y) is approximately 40 degrees. However, many gemological tests cannot be conducted due to the stone’s opacity. Color: Turquoise is famous for its vivid sky-blue hue, which has become a standard color reference. Other shades include dark blue, light blue, lake blue, blue-green, apple green, yellow-green, light yellow, and light gray. The blue color is primarily due to copper, while iron substitution can result in green tones. Water content also influences the shade of blue. Absorption Spectrum: Under strong reflected light, turquoise may show two weak absorption bands at 432 nm and 420 nm, and occasionally a faint band at 460 nm. Fluorescence: Under long-wave ultraviolet light, turquoise may fluoresce with a yellowish-green to blue glow, though short-wave UV fluorescence is less common. No significant luminescence is observed under X-ray. Thermal Properties: When exposed to heat, turquoise tends to crack or shatter, turning brown or green when heated. Chemical Reactivity: Turquoise reacts slowly with hydrochloric acid, indicating its sensitivity to acidic environments. Overall, turquoise is a fascinating mineral with rich historical and cultural significance, valued not only for its beauty but also for its unique physical characteristics. Trailer Home,mobile homes,luxury trailer homes,modular trailer homes Zhengzhou guan hao yong International Trade Co., , https://www.homepipes.com