Turquoise is a hydrous phosphate of copper and aluminum. It is a good example of an opaque colored stone that can be marketed both as a gem for jewelry and as an ornamental material.Its multi-layered history and soul-calming color make it a desirable gem. Earliest record of turquoise as a gemstone comes from Egypt.It has been found in royal burials over 6000 years old Turquoise objects were also held in high regard by Native Americans and were traded widely.

Native American jewelry often features carved turquoise birds and animals, called fetishes. - Courtesy Jaime Steelman

Turquoise Identification

Turquoise can be identified by its distinctive sky blue, blue-green or apple-green color and waxy to matt lustre. It can be distinguished from similar gemstones such as chrysocolla, variscite and smithsonite by its Mohs hardness of 5 to 6.

urquoise Deposits

Most of the world's turquoise rough is currently produced in the southwestern United States, China, Chile, Egypt, Iran, and Mexico. The premium quality turquoise deposit is located in Northeast Iran.

Turquoise Hue

Turquoise is the only gemstone that has a colour named after it. The most-prized turquoise color is an even, intense, medium blue also called "robin's egg blue" or "Persian blue”, followed by blue-green or apple-green.

Turquoise Clarity and Surface

Turquoise is semi-translucent to opaque. It exhibits a waxy to matt lustre. Most turquoise has dark grey, brown or black veiny inclusions of matrix(remnants of host rock). The most desirable turquoise is an even medium blue, with no matrix and the ability to take a good polish. However, sometimes veins form attractive patterns that make it desirable, such as "spider web turquoise".

Turquoise Cut

Turquoise is most often fashioned as a cabochon as these rounded dome shape sets off turquoise’s color, texture, and any matrix beautifully. rough turquoise is also fashioned into round or oblong beads for strand necklaces, and into small, flat pieces that are popular in jewelry inlays.

Turquoise Care and Cleaning

• Turquoise is a porous material, turquoise must be properly cared for in order to maintain its color and lustre.
• Remove turquoise rings before washing hands or engaging in household chores. When dressing it is advisable to put on turquoise jewellery last and remove it first when undressing, to avoid exposure to hairspray, perfume or similar cosmetic products.
• To clean your turquoise ,Dampen a clean, soft-bristled toothbrush in clean water and gently scrub the surface of the stone. Air-dry after toweling to be sure that it is dry.

Turquoise Gemological Properties:

Chemical Formula: CuAl6(PO4)4(OH)8•4H2O Copper containing basic aluminium phosphate

Crystal Structure: Triclinic (seldom); botryoidal aggregates

Colour: Sky-blue, blue-green, apple-green

Hardness: 5 to 6 on the Mohs scale

Refractive Index: 1.610 to 1.650

Density: 2.31 to 2.84

Cleavage: None

Transparency: Translucent, opaque

Double Refraction: 0.040

Lustre: Waxy, matt

Fluorescence: Weak; green-yellow, light-blue