What are the different types of opals?

Opals are among the most popular gemstones for jewelry due to their play of color and versatility. There are many different types of opals, some of which we will go into great detail here. Two of the most known types of opals are Mexican fire opals and Australian opals, of which there are many different varieties.

Let’s dive into these gorgeous gemstones and discover how they’re formed and what specific characteristics they possess.

Mexican fire opals, sometimes just called fire opals, are a beautiful type of opal that can range in color from bright red to almost clear, with different plays of color. The majority of Mexican fire opals come from the states of Jalisco, Querétaro, and Guerrero in Mexico. They are formed in volcanic rock when water rich in silica goes into the cracks in the rocks. When the water evaporates, the silica is left behind, forming the opals, which also accounts for their interesting freeform shapes. Mexican fire opals can vary greatly in color from bright red, orange, yellow, or clear, and within each of these colors exists other flashes of color such as purple, blue, and green. They are most often translucent, which allows the colors to shine even brighter as the light reflects through them.

While fire opals do sometimes contain inclusions, they are not often very visible, due to the unusual shapes and color combinations of the stones. Fire opals have developed great symbolism over time and are associated with passion, optimism, and healing. They can be used for a variety of jewelry and make a wonderful statement piece because of their vivid colors. They are most often seen in earrings and pendants in their freeform state. There are also some fire opals that are faceted, and those tend to be a little less translucent than their freeform counterparts. The faceted stones can be more readily used in traditional style jewelry because they are easier to set, due to their shape.

Because fire opals are a fairly soft stone (compared to diamonds and sapphires, for example) it’s important to take great care with them to avoid damage. They need to be stored in a padded and dust free environment and worn with extra care, not during any strenuous activity where they may be exposed to impact, harsh climates, or chemicals. They should be cleaned carefully with warm water and never placed in an ultrasonic or steam cleaner.

Another popular species of opal is the Australian opal, which comes in many different subtypes. Australia is known for producing over 95% of opals in today’s market and they are most often found in South Australia, Queensland, New South Wales, and Western Australia. All types of Australian opals are known for their distinct play of color, which differs depending upon the body color of the stone and can also be affected by the light source from which it’s viewed.

Australian opals symbolize protection and have been used to keep away evil spirits, which makes them a meaningful gift for a loved one. They are used in a variety of jewelry types due to their wide range of shapes, sizes, colors, and versatility. While opals are not usually faceted, they are cut into cabochons, a shape with a rounded top and flat bottom. They are a fragile type of gemstone and fairly soft, so they need to be treated with care to avoid damage. They need to be kept away from chemicals and harsh temperatures, so only wear them in safe conditions to ensure that they will endure the test of time.

There are a variety of Australian opals:

  • Black Opal: Black opals have a dark body color, which allows for a striking play of color and contrast when in the light.
  • White Opal: White opals have a light body color and usually also show vivid play of color.
  • Boulder Opal: Boulder opals are formed in a specific way that results in them having a built-in rock backing that allows the play of color to show more vividly.
  • Crystal Opal: Crystal opals are most often transparent and display a beautiful play of color.
There are types of opals called doublets or triplets, which refers to when a piece of opal (typically Australian opal) is attached onto a different backing material to provide stability and a dark background for contrast with the play of color. With a triplet, an additional layer of clear quartz is added on top to protect the opal from damage. This type of opal is more prevalently used in jewelry because it’s more stable and less prone to damage. It also makes the stone easier to set because of the stable backing.

There are other types of opals that are not considered precious enough for jewelry use. These are called common opals, and they are characterized by lacking the play of color that makes precious opals so sought after. They usually have one body color and can come in an array of different colors, though not vibrant, and are usually opaque or milky in appearance. While not used for jewelry, common opals have a variety of other uses, such as making beads and carvings. Although common opals don’t fetch as high of a price tag as precious opals, the art that they are used to create can still be quite pricey depending upon the quantity used, the size of the piece, and the artist in question.

Like diamonds and certain gemstones, opals are also available in a synthetic alternative and are grown in a lab. There are different techniques that can be used, including hydrogel, which is when silica is put into water or gel and arranged to mimic an opal. In polymer impregnation, polymer resin and silica are combined to create a material that resembles an opal. The visual appearance of lab grown opals can be controlled by the use of colored dyes to create different colors and patterns. It's even possible to create lab grown opals with beautiful play of color, although it is never quite as sporadic as a natural opal. They can be used in a variety of jewelry and are more affordable than their natural counterparts, making it possible to achieve a similar look with a lower budget. Due to their chemical properties being more closely controlled, synthetic opals are usually stronger than natural opals, but they can still be susceptible to damage if not taken care of properly.

Ultimately, opals are a highly sought after gemstone prized for the beautiful play of color that they can present. Two of the most popular types–Mexican fire opal and Australian opal–can come in a wide array of colors, shapes, and sizes, but share certain characteristics. They, more often than not, have a unique freeform shape and are used in all types of jewelry, however the wearer must be careful because all opals require gentle handling to ensure they don’t get damaged.

If natural opals are over your desired price point, doublet, triplet, or synthetic opals are great alternatives to explore. Any opal you incorporate into a jewelry piece is sure to add a gorgeous pop of color that you’ll enjoy for many years to come