Ethiopian Opal Turned Yellow/Brown - Top 7 Reasons and their Fixes

Ethiopian opals are particularly famous for their fiery play of colors. But do you know what causes these dazzling gems to take on unexpected brown or yellow hues?

Moving forward, we’ll explore the various factors behind these color shifts, from environmental influences to natural properties, and provide valuable insights on how to restore your opal’s original appearance.

So let’s dig in!

Table of Contents

Why Does an Opal Change Color?

One reason for the changing colors in opals is a unique natural phenomenon known as ‘play of colors’. In their internal structure, opals contain tiny spheres of silica.

When light enters an opal, it interacts with these spheres and causes them to diffract light into a spectrum of colors. The color of the opal changes as you view it from different angles or under different lighting conditions.

Secondly, Ethiopian opals are thirsty little rocks, known for their unique hydrophane property. They absorb any liquids or substances that they encounter, and experience changes in color as a result.

Depending on the nature of substances soaked up by the opal, these changes can be permanent or temporary.

In a nutshell, the changes in the color of an Ethiopian opal can stem from its natural characteristics or be induced by interaction with external factors.

Why Did my Ethiopian Opal Turn Yellow – 7 Reasons

Some of the common causes of an Ethiopian Opal turning yellow/brown are as follows:

Water Absorption

Ethiopian opals have the ability to absorb water and temporarily change their appearance.

When opals soak up water, they tend to turn light yellow in color. This change in color, however, is temporary and easily reversible.

Ethopian Opal – Before & After Water Absorption

The original color of the opal is usually restored as soon as it dries out completely. However, in some cases, your Ethiopian opal may not be able to revert to its original color, particularly in situations where chemical substances are also present in the water.

Presence of Stabilizing Resins or Fillers

Some Ethiopian opals have been treated with stabilizing resins or fillers to enhance their strength and appearance.

The color change in the opal typically happens when these resins interact with environmental factors, such as humidity or high temperature, and turn yellow. The yellowing of the stabilizing agents in turn may give your opal a yellowish brown appearance overall.

In short, Ethiopian opal stones treated with stabilizing resins may start to show a noticeable yellowish tinge over time.

Exposure to High Temperature

Opals are sensitive to high temperature, particularly because heat impacts their water content. When the water balance in the opal is disturbed due to prolonged exposure to heat or sunlight, it results in a yellow or brownish appearance of the Ethiopian opal.

Contact with Chemicals

As mentioned earlier, opals are porous stones, which means they have the ability to absorb anything that they come in contact with.

If your Ethiopian opal was exposed to chemical substances, such as those found in everyday household cleaning products or cosmetics, it may induce a color shift in the opal from its original vibrant hues to less appealing yellow-brownish hues.

Ethiopian Opals After Losing Original Color

Wrong Cleaning Method

Due to their porosity, Ethiopian opals are sensitive to a lot of things, and cleaning techniques is one of them. Cleaning your opal in an ultrasonic cleaner or using locally available cleaning chemicals is likely to result in undesirable changes in its appearance.

The cleaning agents and jeweler’s rouge in the ultrasonic cleaner can be absorbed by the opal, and trigger undesirable changes in its color.

Dehydration

Ethiopian opal is a water-loving stone. Although excessive water absorption can make it lose its color, lack of water content due to heat or dry conditions can also make it lose its vibrant appearance and develop an unusual yellow or brownish hue in its color.

Impurities or Trace Elements

Some Ethiopian opal varieties naturally contain impurities that impact their overall appearance with the passage of time. A change in the color of these impurities may give a yellow or brownish appearance to your opal.

Similarly, the presence of trace elements in the internal structure of the Ethiopian opal and their interaction with external factors can also transform the color of the stone.

How Do You Restore the Color of an Ethiopian Opal?

Restoring the color of your Ethiopian opal may not always be possible. But depending on the factors that induced the color shift, you can try out a few methods to get that fiery opal color back.

Let it Dry

If your Ethiopian opal got soaked in water, lost its original color, and turned yellow, don’t worry. The original color of an Ethiopian opal will be restored as soon as it dries. Your stone may take a few hours to several days to dry out completely.

Note: Allow the stone to dry out on its own. Force-drying can harm the opal as it gets exposed to intense heat in the process.

Water Bath

If you live in a hot climate or had your Ethiopian opal exposed to a high temperature, it is natural for the stone to lose its original appearance as the water balance gets compromised.

To restore the color:

Submerge your opal in distilled water for a while.
Monitor the progress periodically and remove the stone when you notice its original color is restored.
Remove the stone from the water bath and let it air dry.

Have It Recut

Recutting involves removing a portion of the opal’s surface and exposing the fresh layer of stone underneath. This process can allow you to enjoy the original color of the Ethiopian opal again.

However, recutting can impact the value of the stone and does not offer guaranteed results, which is why it is almost always recommended as the last resort to restore the color of an Ethiopian opal.

Final Word

Ethiopian opal may turn yellow/brown due to a variety of factors, from environmental influences to internal characteristics. These color changes can be temporary or permanent, but understanding the triggers and knowing how to respond is key to preserving their natural beauty and vibrant play of colors.