Opals are renowned for their unique colour play and remarkable visual effects. This makes them one of the most fascinating jewels that come to mind. With the increasing popularity of synthetic and processed opals, it is important to know how to identify a genuine opal from a fake or enhanced one. Whether you're an expert collector or just starting out, having this information can make your buying experiences more enjoyable. You can tell an authentic opal from a fake by following these helpful tips.
Examine the Finish and Feel the Texture
Opals that are authentic usually have a smooth, waxy surface and a natural feel. Use your fingertips to caress the stone. The finish shouldn't be too smooth or synthetic. There shouldn't be any obvious paint, pigment, or coating flaws that would indicate a fake.
Poorly cut natural opals may have a rough texture, but their characteristic dance of colours will still be visible. A surface that feels like glass or plastic might be caused by an artificial top layer or synthetic triplet.
Analyse the Colour Play
The opalescence, or colour play, of opals is one of its most striking characteristics. Real opals may show a wide spectrum of colours, some of which shift and vary depending on the light and the viewer's point of view.
You can tell it's not real opal if it has a uniform coloration or lacks the natural lustre that is characteristic of genuine opals.
Search for Doublets and Triplets
Partial synthetic composites that resemble solid opals are known as doublets and triplets. A thick slice of genuine opal adhered to a dark substrate, such as ironstone or black potch, forms a doublet. Triplets, for the sake of both safety and aesthetics, add an additional transparent layer on top, often made of quartz or acrylic. Where can I find them?
Under bright light, examine the stone's face; inclusions such as doublets and triplets often reveal the underlying layers that connect the various parts.
Check the Back of the Opal
If the background is black or grey and composed of vitrolite, plastic, or glass, then the opal is not solid but a doublet or triplet.
Spot the Bubbles
Tiny air bubbles created during the production process are common in synthetic opals. Carefully examine the stone using a magnifying glass or jeweller's loupe. You can tell it's not real opal if it has bubbles. Contrarily, these flaws are not uncommon in genuine opals (though bubbles specifically are more indicative of synthetics or glass imitations).\
Assess Hardness
On the Mohs scale, opals fall anywhere between 5.5 and 6.5. Carefully scratch a hidden spot on the stone with the blade of a knife or something similar (Note: This is a destructive test and generally not recommended unless you own the stone and accept potential damage).
Although it is not as scratch-resistant as harder gemstones like quartz, genuine opal outperforms softer materials like plastic. You can tell it is fake if it scratches too readily.
Find Any Unusualities on the Surface
Natural opals often have surface imperfections and inclusions formed during their creation, whereas synthetic stones tend to seem flawless. Look for indications of natural characteristics on the stone. A genuine opal may include surface flaws such as swirls, potch lines, or other natural irregularities.
Try It Out in Water
The results of a water test may be useful in determining the authenticity of an opal, albeit they are not always definitive, especially for treated opals. Genuine opals are inherently porous to varying degrees; thus, they might absorb water over time when you put a few droplets of water on their surface (hydrophane opals are particularly known for this).
If water beads up and stays on top, it might mean the stone is man-made, a doublet/triplet with a sealed top, or treated.
View with a Magnifying Glass
Under a 10x loupe, the opal's distinctive features become more apparent. Small flaws, like inclusions or play-of-colour anomalies (like columnar or snakeskin patterns in synthetics vs. more random patterns in naturals), are common in naturally occurring solid opals.
If the patterns on synthetic stones are uniform or unnaturally perfect, they might seem unrealistic.
Observe Transparency
Opals may have a range of translucencies. True opals frequently show internal depth and are semi-transparent or translucent (though some, like black opal, can be opaque). If the stone is unusually opaque or has an unusually flat appearance, it may not be an opal, or it could be a doublet/triplet.
The light that passes through or reflects off a real opal will make its colours pop.
Get Professional Advice
If you remain unsure about the opal's authenticity, please consider consulting a trained gemologist. Experts use certain instruments and procedures that may provide irrefutable proof of the stone's composition and origin.
They can do tests you can't easily do at home and give you an official evaluation.
Shop with Reliable Vendors
The most important thing is to purchase from a reliable jeweller or supplier if you want to be sure you're obtaining a genuine opal. To have faith in the authenticity of your purchase, seek vendors that provide clear information and potentially authenticate their stones.
Speaking of reliable vendors, discover a stunning collection of authentic Opal Jewellery in Sydney at Cove Jewellery.
Identifying a genuine opal from a fake requires experience and a keen eye. By following these guidelines to properly inspect any opal before buying it, you can prevent scams and ensure that you have a beautiful, authentic gemstone in your collection.