This beautiful gemstone was once considered an economical, yet strikingly beautiful substitute for diamond and occurs naturally in yellows, browns, greens and can also be colorless. The color is determined by the presence of several earth elements such as uranium and thorium and the presence of these radioactive elements can affect the crystal structure of the stone thereby changing the clarity. Blue and red stones can occur naturally but are considered to be very rare and therefore highly prized. Modern methods of artificially treating brown, green or colorless stones, mostly by heating, produce beautiful shades of blue and red. Gem quality stones are becoming harder to find. In recent years, zircon has fallen victim to mistaken identity and has very often been confused with the synthetically manufactured and cheaper cubic zirconia.

Properly cut and polished, these stones emit a brilliance and clarity that rivals many of the more expensive gemstones. Though blue zircon can be found in nature, most of the blue stones for sale on the market today are the result of heat treating. A relatively hard stone, it makes a durable gemstone for most jewelry.

History

Zircons are found in a wide variety of locations around the world including Scandinavia, the United States, Canada, Russia, and throughout Southeast Asia. The Arabic name for zircon, zar or gold, appears as early as the Middle Ages. A piece of zircon is thought by some to be the oldest stone found on the Earth and is estimated to be over four billion years old.

Birthstone Information

Zircon has long been recognized as the birthstone for the month of December. Blue zircon is considered a less expensive though certainly adequate substitute for blue tanzanite which was recently added to the list of December stones, sharing the honor with turquoise.

New Age Beliefs and Powers Through The Ages

Like many other stones and crystals with an ancient past, this stone is the stuff of myth and lore. The Middle Ages were a time when the plague or Black Death ravaged many parts of Europe and the Near East. Among its other healing and metaphysical properties, it was thought to protect the wearer from death by the plague. Since many believed that travelers were responsible for spreading the plague, traveling while wearing zircon as an amulet this stone became an important symbol of personal protection. Many people believed that the wearer would also be protected from injury and other misfortunes while on their journey. Wearing this stone was thought to impart wisdom and honor as well as ward off insomnia and other physical maladies.

Artificial Forms of Enhancement

Heat treating is a common method used to change the color of these stones. Heating in the presence of oxygen or other gases can produce dazzling blue, deep red and yellow stones.

General Scientific Information

The chemical name ZrSiO4 zirconium silicate

Hardness measures 6.5 to 8.0 on the Mohs scale - the Mohs scale measures the hardness of metals, minerals, gemstones and crystals on a scale of 1 to 10. For example the hardness properties of most quartz crystals fall around 7 on the scale, as does steel and titanium. Diamond is the hardest known substance on the Mohs scale coming in at a hard 10. To most consumers hardness generally reflects the stones able to resist scratches and cracks.

The cleavage of zircon is imperfect.

The index of refraction ranges from a low of 1.78 to a High of 2.01and generally indicates the purity of the stone.

The specific gravity ranges from a low of 3.9 to a high of 4.80.

The crystalline system is tetragonal.