Posted on by Nevil Agrawal

Chalcedony was named after an ancient Greek town called “Chalkedon” in Asia Minor. The name “chalcedony” is believed to have derived from the Latin word “chalcedonius”. An oxide mineral from the quartz group, chalcedony, contains a variety of beautiful gemstones that are formed during the volcanic eruptions in igneous, sedimentary and metamorphic rocks.

Often carved to make official seals, chalcedony has a long history and is wrapped in rich folklore. The Romans used it to make seals, amulets and signet rings, while Native American Indians used it for ceremonial purposes. With time the uses of this stone have changed, but the desire for it has only increased.

All the semi-precious stones from the chalcedony group are tough, which is why they are quite popular for making different ornaments and jewelry. Here is a buying guide that will tell you everything about chalcedony and how to identify a real one.



chalcedony cabochons


What is chalcedony?


Chalcedony is a cryptocrystalline form of silica that is composed of very fine intergrowths of quartz and moganite. This microcrystalline type of quartz has many varieties and every variety has a different color. Here are some of the classic varieties of chalcedony –

  • Agate – A multicolored banded variety
  • Aventurine – Mostly green in color
  • Bloodstone – A dark green to blackish-green variety with brown or red spots
  • Carnelian – An orange variety, can also appear reddish-brown
  • Chrysoprase – An apple-green variety that may also be deeper green in color
  • Jasper – Typically red, brown, green and yellow, rare blue specimens can also be found
  • Onyx – Can be red, orange, or brown with white bands
  • Sard and Sardonyx – Sard is yellow to brown and sardonyx is found in multiple colors like gray, black, brown, yellow, white, purple, pink and green
  • Tiger’s eye – A golden-brown variety with golden stripes


Where is chalcedony found?


Found in the sedimentary rocks or volcanic environment, the most significant source of chalcedony is the United States. There are other sources of this gemstone, too, including Uruguay, India, Madagascar, Myanmar, Mexico, Brazil, and Southwestern Africa.


How to identify chalcedony?


Whenever buying chalcedony, keep in mind that it is always translucent and appears in solid, lighter shades that range from blue to white or gray. Chalcedony stones also possess slight piezoelectricity, just like tourmaline, and therefore can carry a small electrical charge. It is easy to distinguish chalcedony from other stones, but due to many varieties of this stone, it is sometimes difficult to differentiate it from its own kind. Therefore, for identification within the chalcedony family, it is important to keep the properties and colors of each variety in mind.


What are the varieties of chalcedony?


agate gemstone


  • Agate

Agates come in numerous shades, including brown, white, red, gray, pink, black, and yellow. This variety of chalcedony is highly popular due to its varied color band. The concentric and curved bands of this rock make it more appealing to the jewelry-makers. The agate too has sub-varieties, including moss agate, plume agate, dendritic agate and fire agate. They differ from each other due to the change in the composition of impurities.

carnelian gemstone
  • Carnelian

Carnelian stone is identified by its translucency and its orangish-reddish tone with mixed hues of brown. Carnelian stones can sometimes be confused with sard or jasper due to their similar properties, but since jasper is an opaque stone, it is differentiated easily. The stone is mostly seen in solid colors, but some specimens may come with dark patches or stripes.


chrysoprase gemstone



  • Chrysoprase

Chrysoprase can appear from nearly opaque to transparent. This apple-green variety of chalcedony is often referred to as ‘the stone of venus.’ The impurities of nickel silicates or nickel oxide in the composition make this stone green in color. Due to its high-quality source from Queensland, Australia, it is also called the Australian ‘jade’.


  • Heliotrope or Bloodstone

Widely known as bloodstone due to the red inclusions it comes with, this stone appears in dark green shades, displaying a vitreous luster when polished. Some heliotropes may also be blackish-green in color.


  • Chrome chalcedony

Colored by small amounts of chromium, chrome chalcedony is a green variety of chalcedony. Called Mtorolite, Mtorodite, or Matorolite in its main source Zimbabwe, the stone is often confused with chrysoprase.

onyx gemstone
  • Onyx

Onyx is a parallel banded oxide mineral. The stone comes in a variety of colors, including white, black, gray, red, and brown. Sardonyx is also a type of this stone that comes with bands of sard colors, while cornelian onyx includes color bands of carnelian colors. Onyx is identified with its translucent appearance, vitreous luster, and a white streak.


Chalcedony – Metaphysical properties, uses, and benefits.


Chalcedony contains healing elements that are believed to provide the endurance to the body and boost the stamina as well. Offering an emotional balance, it encourages responsiveness, receptivity, kindness, generosity, and friendliness. It also helps in relieving fever symptoms, aiding eye illnesses, and leukemia. The stone is also believed to promote lactation in breastfeeding mothers and helps in the treatment of dementia and Alzheimer’s. Since ages, chalcedony has been used in handicrafts, tools, and ornaments. Currently, the widespread use of chalcedony in different types of jewelry has increased its demand. From rings and pendants to necklaces, it is suitable for every jewelry because of the beautiful colors it is available in.


The Qi or Prana, also known as the chakras, are the energy centers of the body that influence mental, emotional, or physical well-being. The seven chakras are regulated through colors.

  1. Crown Chakra – Purple
  2. Third Eye Chakra – Indigo
  3. Throat Chakra – Blue
  4. Heart Chakra – Green
  5. Solar Plexus Chakra – Yellow
  6. Sacral Chakra – Orange
  7. Root Chakra – Red

Chalcedony is believed to be connected with the throat chakra. It relieves the wearer from sore throat or throat infections. Due to its association with the throat chakra, the stone also helps in communication, allowing the wearer to express emotions and feelings comfortably.

The 4 C’s of Chalcedony


  • Color
The chalcedony group usually appears white to Quartz impurities, most often including iron, nickel, copper, and titanium, affect the color tones of chalcedony and its varieties. It is also seen in hues of tan, blue-white, yellow, buff, gray, or brown. All the colors of chalcedony are spread uniformly throughout its surface.


  • Clarity 

Chalcedony is translucent to opaque and displays a waxy, vitreous, or dull luster when polished. If the stone features a cloudy distribution, it reflects the originality of chalcedony gemstone as long as it doesn’t affect its translucency. It is generally milky when it comes to appearance and may have slight inclusions or fractures, but they are not visible to the naked eye. Chalcedony’s outer surface rarely has any cracks on it.


  • Cut 

Chalcedony is a tough stone and comes with a hardness of 6 – 7 Moh. Typically cut en cabochon to intensify the glow, the most popular shapes of chalcedony include oval, round, and cushion. Tumbled stones and drilled beads are other fancy types of chalcedony that are coveted by many.


  • Carat 

Colored stones often vary in size-to weight ratio, therefore while buying chalcedony, go with the size and not by carat weight.


Chalcedony Treatments


Being typically porous, chalcedony can receive heat treatment or is dyed to alter its color. Irradiation is not very common, but still, it is used for different specimens of chalcedony. Usually, the ‘actual chalcedony’ does not receive any treatment, but some varieties of it are enhanced, like dyed agate. Chalcedony can easily imitate other gems when dyed, but mostly the treatment is done to replicate a variety of itself like carnelian or banded agate. Bleaching can also enhance the color of chalcedony.


chalcedony gemstone


How to clean chalcedony?


You can easily clean this stone with warm soapy water and a brush. Chalcedony is a tough stone, but it can get scratched, so be careful not to use a scrubber or other hard objects for cleaning. Store in fabric-lined boxes or wrap them in soft clothes. Keep this stone away from chemicals, especially while doing household work. Make sure not to expose the stone to direct heat; it may cause permanent damages.


Facts about chalcedony


  • Chalcedony was also called “Mecca Stone” and “St. Stephan’s stone” in ancient times due to its heavenly blue color.
  • In the Bronze Age, chalcedony was used in the Mediterranean region to make seals because the stone wouldn’t stick to hot wax.
  • It is said that the Jewish High Priest, Aaron’s breastplate that represented the 12 tribes of Israel, had at least 3 varieties of chalcedony. They were jasper, chrysoprase and sardonyx.
chalcedony connectors


Where to buy chalcedony from?


At GemsforJewels, we offer chalcedony gemstone in fourteen beautiful shades, including white, gray, and blue. Buy these stones loose, as cabochons, connectors, or even as strands; there are many varieties to choose from. You also have different shapes to pick from, and your options include round, oval, pear, rectangle, and nine other exciting shapes. Chalcedony set in rings, necklaces, and earrings will be loved by your customers.


Our services also include customization on orders to suit your preferences. Select your chalcedony gemstone at GemsforJewels and experience our unparalleled services.