Water played a very significant part in the formation of Australian Opals. Without water, the Australian opal mining locations would not exist. Australian Opal was formed from a chemical reaction of silicon dioxide and water. Why was water in the Australian outback and dessert you ask? Actually Australian once had a giant inland sea known as the Great Artesian Basin. This area was the result of the formation of Australian Opal in the land. As the water run down through the earth, it picked up silica from sandstone, and carried this silica-rich solution into cracks and voids. As the water evaporated, it left behind a silica deposit. These deposits have formed a shiny rock appearance with different colors and patterns that people refer to as Opals.
In this blog, I will explain everything there is to know about the differences between Opals and Water, Opals Wet with Water and Water Opals.
What are Water Opals?
Water opals, also known as hydrophane opals, are a type of opal that can absorb water. When immersed in water, they become temporarily transparent, revealing vibrant colors and patterns. Once they dry, they return to their original appearance. This unique characteristic makes them distinct from other types of opals. It is important to note that there is no such thing as an Australian Water Opal, as there are no Australian Hydrophane Opals. The only exception to this is a small volcanic formed hydrophane opal mine near the popular tourist town of Byron Bay called Tintenbar (Tintenbar Opals). There are very few opals from this location ever on the market.
If you see an Australian Opal labeled as a Water Opal, it may just be the sellers marketing tactic; ie a blue opal that looks like it is the color of water. We often label a lot of our blue opals as Ocean Opals. Other variants include Reef Opals, Beach Opals or Deep Ocean Opals. These names are purely formed for marketing purposes to apply to a specific demographic of people – ie ocean lovers.
Wet Rough Opals
Showing rough opals with water on them is a common practice in the gemstone industry because it enhances the visibility of the internal colors and play-of-color within the stone. When uncut/unpolished opals are wet, their colors become more vibrant, making it easier for gem cutters, dealers, and buyers to assess the stone’s potential and quality. This temporary wetting of rough opals allows for a better understanding of the gem’s characteristics before it is cut and polished. You will almost always see rough or rubbed down opals for sale either wet or in water. It is recommended for the savvy buyer to also inspect the rough or rubbed opals dried out however, as this may expose some cracking or crazing that the water will hide.
Mexican Water Opals
Mexican water opals refer to opals found in Mexico that possess hydrophane properties. These opals can absorb and temporarily become transparent when submerged in water. In some instances you may even see a bubble of water inside of the opal. Mexican opals, in general, are known for their play-of-color, which is the phenomenon where the gemstone displays a spectrum of colors as it interacts with light. The hydrophane variety from Mexico adds the unique feature of transparency when wet.
Ethiopian Hydrophane Opals
Ethiopian water opals, similar to Mexican water opals, are a type of opal known for their hydrophane properties. These opals can absorb water, becoming temporarily transparent and revealing vibrant colors when wet. Ethiopian opals, in particular, gained attention in the gemstone market for their impressive play-of-color, which is the phenomenon where the opal displays a spectrum of colors as it interacts with light. The hydrophane feature adds an intriguing dimension to these opals, however beware that they can lose their colors as a result to changes in climate. If your looking for a life long opal that will stay the same forever, we recommend purchasing an Australian Opal over any type of hydrophane opal.
Storing Opals in Water
Opals, especially hydrophane opals, are sometimes stored in water to prevent them from dehydrating and developing cracks. Opals contain water within their structure, and when exposed to dry conditions or extreme temperature changes, they can lose this internal water content, leading to a loss of play-of-color and potential cracking. Storing opals in water helps maintain their hydration and structural integrity. It’s essential to note that not all opals require water storage, and some may be more stable in different conditions. All opals are different and its important to understand the type of opal. In no instances are opals required to be kept in baby oil, or water with oil inside. I have seen this happen on many occasions and it will make the opals difficult to cut (if they are in rough form).