RUBY

Ruby is the most valuable variety of the corundum mineral species, which also includes sapphire.

OVERVIEW

Rubies can command the highest per-carat price of any colored stone. This makes ruby one of the most important gems in the colored stone market. In its purest form, the mineral corundum is colorless. Trace elements that become part of the mineral’s crystal structure cause variations in its color. Chromium is the trace element that causes ruby’s red color.

Ruby is the most valuable variety of the corundum mineral species, which also includes sapphire. Rubies can command the highest per-carat price of any colored stone. This makes ruby one of the most important gems in the colored stone market.

In its purest form, the mineral corundum is colorless. Trace elements that become part of the mineral’s crystal structure cause variations in its color. Chromium is the trace element that causes ruby’s red, which ranges from an orangy red to a purplish red.

The strength of ruby’s red depends on how much chromium is present—the more chromium, the stronger the red color. Chromium can also cause fluorescence, which adds to the intensity of the red color.

The most renowned rubies, like those from Myanmar, the Himalayas, and northern Vietnam, typically form in marble. They’re found in layers that are distributed irregularly within the surrounding marble. Marble forms as part of the metamorphic (rock-altering) process, when heat and pressure from mountain formation act on existing limestone deposits.

WHERE IS IT FOUND ?

Our search for the July birthstone starts in Myanmar (formerly known as Burma), one of the oldest recorded sources of fine rubies. For more than five centuries, the Mogok area in Myanmar has produced some of the most sought-after rubies – vibrant red beauties softened by light-scattering inclusions and a glowing red fluorescence. The region is a place of weathered marble and ancient Buddhist temples.

Since the late 20th century, Vietnam has been another important source for the July birthstone. The Luc Yen region in northern Vietnam, where rainforest-clad mountains rise over broad paddy fields, produces rubies of red to purplish red color. Farther south, the Quy Chau district has also yielded many fine rubies. Today, artisanal miners work the soil in hopes of finding a gem that will change their fortunes.

Mozambique is an important new source for the July birthstone. This African nation is home to the prolific mines at Montepuez. Rubies found there have been compared to the famed gems of Mogok.

For many years in the late 1900s, the ruby deposits along the border between Thailand and Cambodia were the major source of rubies in the marketplace. Other important producers of the July birthstone include Afghanistan, Tajikistan, Pakistan, Sri Lanka, Kenya, Tanzania and Madagascar.

CARE & CLEANING

Rubies are often heat treated to remove purplish coloration, leaving a purer red. The process can also remove “silk” (minute needle-like inclusions) that can cause a gem to appear lighter in tone and be more opaque. The trade typically accepts heat treatment, as it is stable to normal conditions of wear and care. However, rubies may also be subjected to lattice diffusion treatment and dyeing. In lower-quality material, surface-reaching fractures and cavities may be filled with a glass to decrease their visibility so the gem appears more transparent. Some of these treatments may make the ruby more vulnerable to damage during normal wear and care.

Before you buy, always ask if your ruby has been treated and by what method. The Federal Trade Commission requires disclosure of treatments that affect a gemstone’s perceived value. A GIA Identification Report is important in identifying if a stone is natural or synthetic and whether it has been treated in any fashion.

In most cases, the July birthstone can be safely cleaned with warm soapy water and a soft brush. Ultrasonic and steam cleaners are usually safe for untreated, heat-treated and lattice diffusion–treated stones. Glass-filled or dyed stones should only be cleaned with a damp cloth.

HISTORY

Red is the color of our most intense emotions—love and anger, passion and fury. It’s associated with objects of power and desire—like fast cars and red roses. Early cultures treasured rubies for their similarity to the redness of the blood that flowed through their veins, and believed that rubies held the power of life.

Ruby is one of the most historically significant colored stones. Rubies are mentioned four times in the Bible, in association with attributes like beauty and wisdom. In the ancient language of Sanskrit, ruby is called ratnaraj, or “king of precious stones.”

In the first century AD, the Roman scholar Pliny included rubies in his Natural History, describing their hardness and density. Ancient Hindus believed that those who offered fine rubies to the god Krishna were granted rebirth as emperors.

Hindus divided ruby into four castes, calling the true Oriental ruby a Brahmin. Someone in possession of a Brahmin was believed to have the advantage of perfect safety.

Ruby has accumulated a host of legends over the centuries. People in India believed that rubies enabled their owners to live in peace with their enemies. In Burma (a ruby source since at least 600 AD—now called Myanmar), warriors possessed rubies to make them invincible in battle. However, it wasn’t enough to just wear the rubies. They had to insert them into their flesh and make them part of their bodies.

The name ruby comes from the Latin word ruber, which means “red.” The glowing red of ruby suggested an inextinguishable flame burning in the stone, even shining through clothing and able to boil water.

Ruby has been called the most precious of the 12 stones created by God.

Ruby retained its importance with the birth of the western world and became one of the most sought-after gems of European royalty and the upper classes. Many medieval Europeans wore rubies to guarantee health, wealth, wisdom, and success in love.

Desire for ruby is just as great today as it always has been. As a symbol of passion, ruby makes an ideal romantic gift. Consumers are drawn to the lush color because it also signifies wealth and success.

BIRTHSTONE

Ruby is the birthstone for July and the gem for the 15th and 40th anniversaries.

FACT SHEET

Mineral: Corundum
Chemical composition: Al2O3
Color: Red
Refractive index: 1.762 to 1.770
Birefringence: 0.008 to 0.010
Specific gravity: 4.00 (+/- 0.05)
Mohs Hardness: 9

Source of Content : www.gia.edu