Most agates formed in cavities of ancient lava flows and in eruptive rocks (rocks that came from a volcanic eruption). Agates form when gas bubbles become trapped in the solidifying lava and then become filled with alkali and silica-bearing water. Many agates have a banded structures and are characterized by peculiarities in the shape and color of the bands,

The alkali attacks the iron in the surrounding lava, and bands of the resulting iron hydroxide are created in the gel, which loses water and crystallizes, leaving the bands intact. Many agates, when cut in cross-section, reveal striking forms.

There are dozens of varieties of agate with varied names usually given to each. Because of the nature of its formation, almost every piece has its own distinct pattern of swirls, band and / or inclusions. Here are a few of the many named varieties of Agate:

Agatized Coral is a result of Coral in an Agate compositions and is often referred to as Petoskey Agate or Petoskey Stone.

Fire Agate is a variety of Chalcedony which was created as a result of ancient volcanic eruptions.

Saginite is a type of Chalcedony Agate that has plant or other material within it that has became part of the stone. Sometimes these inclusions are arranged in needle-like formations and command premium prices.

Turritella Agate is a formation of fossil Turritella shells with a Chalcedony base.

Because of the diversity of color and types of Agates, every fine jewelry collection should have several representative examples of Agate.

Colors and Sources:
Agates occurs in almost all colors including blue, black, brown, gray, green, pink, reddish, and yellow. In addition to the colors, there is an equally wide spectrum of opacity ranging from transparent to opaque.

Agates are found worldwide with Brazil, Egypt, Germany, India, Madagascar, Mexico, Russia, the United States of America and Uruguay being the most active sources for modern Agate mining.

Sources Note:      Due to current political conditions, all imports (including gemstones) from some countries are not permitted under United States law. In accordance with the law, none of the gemstones offered by CAB-FineJewelry are known to be from these countries. CAB-FineJewelry does not knowingly purchase, trade, sell or giveaway goods from any country embargoed by the United States of America. As individuals we may not agree with some of the laws of our great country. However, rather than breaking the law, we choose to work toward changing these laws in a orderly and legal manner and encourage you to do the same. 

Care:
This gemstone should be sparingly cleaned using lukewarm, mild, soapy water and rinsed with the same temperature water. Avoid exposure to strong light and sudden changes of temperature. As with all fine jewelry, remove before doing any type of physical work. Traditional gemstone procedure of storing in soft cloth away from other articles of jewelry hold true, too. While ultrasonic cleaners, steam cleaners and some chemicals could be used on this durable gemstone, we do not recommend their use. Hair-spray and perfumes can leave permanent residue on all gemstones so be sure to keep your jewelry far away from these common items.

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