The Significance of Opal’s Value

Opal Popularity

Opals are a favored choice among jewelry aficionados and specimen collectors. There are even TV shows dedicated to those searching for the rare black Opal. But the fascination with Opal is not just a modern-day phenomenon; its captivating colors have been admired for centuries, along with the mystical qualities various cultures have attributed to it.

Opal in the Past

Numerous cultures have sought after opals for their supposed mystical properties. Ancient beliefs suggested that Opal had supernatural origins due to its unique formation. For instance, in Arabic lore, opals were thought to fall from the sky in flashes of lightning. The Greeks believed that opals could protect their owners from illness and grant prophetic abilities. Throughout history, opals have symbolized hope, truth, and purity, and they have long been regarded as the luckiest gems because of their ability to display all the colors of the rainbow.

Opal Today

In contemporary times, opals are recognized as the birthstone for October, though some hold the superstition that wearing opal is unlucky for those born in other months. Today, opals still represent purity and hope, and we now know that there are two main types: common Opal and precious Opal.

What is Opal?

Opal is a prized gemstone frequently sourced from Australia, consisting of a silica and water mix, also known as a hydrated silicon dioxide mineraloid. The silica forms tiny spheres that diffract light, causing the gemstone to exhibit rainbow colors—a characteristic feature of precious Opal.

In contrast, common Opal lacks these vibrant displays and typically exhibits a singular color. Sometimes, precious and common opal can be found together; this is referred to as potch. Potch and common Opal generally hold little value. Precious Opal, however, can range in colors from white to black, including hues like green, blue, or pink, and will exhibit a “play of color.”

Opal Pricing

The value and cost of an opal can vary based on several factors. Each opal’s unique properties contribute to its overall worth.

Color

The predominant color in an opal is often a key determinant of its value. The size of silica spheres within the opal influences its color, with larger spheres showing reds and oranges, and smaller ones displaying blues and greens. An opal with uniformly arranged spheres will have more intense colors. Opals featuring a red display are the most valuable, followed by those showing orange, yellow, green, blue, and violet. However, the brightness of the opal also plays a crucial role; a vivid blue or green can be more valuable than a dull red or orange. This is why black opals, with their dark body tones, are highly sought after since they make colors appear brighter and more intense.

Clarity

Clarity in opals differs from other gemstones where inclusions or blemishes are a primary consideration. Instead, transparency is more critical, with inclusions being secondary. Opals can range from nearly transparent to completely opaque. Depending on the type, transparency’s value varies. Crystal opals, usually white or colorless, are more valued if they are transparent.

Conversely, black opals are more desirable when opaque, as this best showcases their play of color. Inclusions like common opal mixing with precious Opal or milky clouds can lower the stone’s value.

Carat

Opals come in various sizes, from small to large. Smaller opals are ideal for engagement rings, and despite their low density, even larger opals are lightweight and comfortable to wear. The “Fire of Australia,” the most valuable opal, weighs just under 5,000 carats.

Cut

Cutting opal involves careful consideration of its clarity, color, and pattern to achieve the best play of color. This is why opals often have irregular shapes rather than conventional gem cuts. Though, for average-quality jewelry, opals are typically cut into symmetrical ovals with domed surfaces to prevent breakage if used in cabochon form.

Popular Opal Shapes

• Oval

• Round

• Pear

• Marquise

How Much Does Opal Cost?

The price of opal is largely influenced by its body tone and color play. As noted, opals with dominant red and orange hues are more valuable, and those with black body tones fetch higher prices. Bright, fiery stones are more expensive than dull ones, and similarly to other gems, larger high-quality opals are more costly than smaller ones.

Opal Treatments

Treatments can affect an opal’s value, usually diminishing it. Some opals are heat-treated to improve durability, while very porous opals may be treated with resin to fill open spaces or infused with graphite carbon to darken their body tone. Treatments like sugar solutions, followed by sulfuric acid baths, aim to mimic black opal hues. Historically, methods like charcoal burning and smoke treatment were used to achieve these effects. Generally, it is advisable to avoid opals which have undergone such treatments.