Agate is a type of chalcedony, which is a mineral group that includes gemstones like aventurine, bloodstone, carnelian, chrysoprase, jasper, and others. It is the banded variety of chalcedony and comes in a wide variety of colors, including shades of red, orange, yellow, green, blue, purple, and pink, as well as black and white. Agates are primarily formed within volcanic and metamorphic rocks. The ornamental use of agate was common in Ancient Greece, in assorted jewelry and in the seal stones of Greek warriors, while bead necklaces with pierced and polished agate date back to the 3rd millennium BCE in the Indus Valley civilization. Agate is a versatile gemstone that is often used in jewelry making due to its durability, with a Mohs scale hardness rating of 6.5-7. It is known for its colorful, banded patterns and wide range of hues. Agate is generally more affordable than other gemstones.
Agate is found all over the world, including in the US, Brazil, Germany, Uruguay, Austria, Canada, Chile, Iraq, Morocco, New Zealand, Portugal, Russia, South Africa, Thailand, and more. The metaphysical properties of agate aren’t exactly set, as some may vary depending on a person’s belief system and the exact type of agate involved. However, many consider agate a grounding stone that is soothing or calming and helps balance positive and negative energies. Agate is also believed to be a stone of self-reflection and perception, allowing a person to improve their well-being and identify challenges or obstacles that are holding them back, creating opportunities for correction.
Varieties of agate are characterized by peculiarities in the shape and color of the bands, which are seen in sections cut at right angles to the layers. Some popular collector forms of agate include nodules or geodes sliced in the middle into two polished cross-sections, or thin slabs from nodule or geode cross-sections. Some types of agate include:
- Agatized Coral: A fossilized coral that has been replaced by agate.
- Dendritic Agate: A type of agate that contains fern-like inclusions of iron or manganese, called dendrites.
- Turritella Agate: Contains silicified shells, leading to unique patterns within the stone.
- Moss Agate: A variety having included matter of a green color, embedded in the agate and disposed in filaments and other forms suggestive of vegetable growth.
- Onyx: A type of agate with white bands alternating with bands of black, brown, or red.
In general, agate values are quite modest, and their prices reflect mainly labor and artistry rather than the value of the material itself.
