How to choose Australian Opal

A Simple Guide to Buying Australian Opal

By Jack the Jeweller

Australian opal is one of the most captivating gemstones found anywhere in the world.

Its shifting colours, natural patterns, and individuality make it unlike any other stone used in jewellery.

Many people find buying opal is both exciting and a little overwhelming because every stone is so different, it can be difficult to know what to look out for or how to judge quality.

This guide is designed to help you understand how Australian opal forms, what makes an opal valuable, and how to choose a stone with confidence.

What Is Opal?

Opal is a natural gemstone formed over millions of years when silica-rich water slowly deposits microscopic silica spheres inside rock formations.

When light enters the stone and interacts with these tiny spheres, it creates a beautiful optical effect known as opalescence.

The common term used in the opal industry is play-of-colour, which describes the flashes of colour that appear as the stone moves in the light.

These colours can include red, orange, yellow, green, blue, and violet, often appearing to move across the surface of the stone as it is viewed from different angles.

Because the internal structure of every opal forms slightly differently in nature, no two opals will ever display exactly the same play-of-colour and brightness.

This natural individuality is one of the reasons opal jewellery is so special.

Why Australian Opal Is So Highly Valued

Australia produces the majority of the world’s precious opal and is widely regarded as the home of the highest quality material.

Australian sedimentary opal is known for its stability, durability, and vibrant colour display, which makes it particularly well suited for jewellery.

Unlike some other types of opal found around the world, Australian opal has a stable chemical structure and is non-porous, meaning liquids cannot enter or alter the stone.

For this reason, Australian opal has long been the preferred choice for fine jewellery.

Types of Australian Opal Used in Jewellery

Australia produces several types of precious opal, each with its own unique character.

Black Opal

Black opal is considered the most valuable and rare type of opal. It is most famously found in Lightning Ridge in New South Wales.

The dark body tone of the stone allows the colours to appear stronger and more vivid, creating dramatic flashes of play-of-colour.

Crystal Opal

Crystal opal is transparent or semi-transparent and often displays bright colours that seem to glow within the stone.

When viewed in different lighting conditions, crystal opals can show remarkable depth and movement.

White Opal

White opal has a lighter body tone and softer, but still brilliant colour display.

Primarily found in Coober Pedy, South Australia, it is one of the most recognisable forms of opal and has been used in jewellery for many generations.

Boulder Opal

Boulder opal forms naturally within iron and sandstone deposits in Queensland, Australia, where thin seams of opal run through the host rock.

The ironstone backing provides natural support and contrast, often producing striking patterns and strong colour flashes.

What Determines the Value of an Opal?

Several natural characteristics influence the value and desirability of an opal gemstone.

Understanding these factors can help when choosing a stone.

Brightness

Brightness describes how intense and vivid the colours appear within the opal.

Stones with strong brightness are generally more valuable because the colours remain visible even in lower lighting.

Play-of-Colour

Play-of-colour refers to the range and movement of colours within the stone.

Some opals display only a few colours, while others show a full spectrum of colour across the surface.

Rare colour combinations, particularly those including red or orange, are highly prized.

Pattern

Opals display many natural colour patterns created during formation.

Some patterns are quite rare and can significantly increase the desirability of a stone.

Body Tone

Body tone refers to the base colour of the opal.

Darker body tones often make the colours appear brighter and more vivid, which is why black opal is typically considered the most valuable.

Size and Shape

Large opals with strong colour and brightness are naturally rarer than smaller stones, which can increase their value.

Australian Opal vs Ethiopian Opal

Many people ask about the difference between Australian opal and Ethiopian opal.

Australian sedimentary opal is non-porous and chemically stable, which means liquids cannot enter the stone or affect its appearance.

Ethiopian opal is often hydrophane, meaning it can absorb liquids because of its porous structure. When this happens the appearance of the stone can temporarily or permanantly change.

For jewellery that is intended to last for many years, Australian opal is widely regarded as the more stable and reliable choice.

How to Choose an Opal with Confidence

Choosing an opal is often a very personal experience.

While factors such as brightness, colour, and pattern are important, the most important thing is how the stone makes you feel when you see it.

Some people are drawn to strong flashes of colour, while others prefer subtle patterns that reveal themselves slowly in the light.

Because every opal is unique, selecting a stone that you genuinely connect with is often the best approach and will produce a piece of jewellery that can be loved for many generations.

Caring for Australian Opal Jewellery

Australian opal is suitable for jewellery and can be worn regularly when treated with reasonable care.

A few simple habits will help keep your jewellery in excellent condition.

• Avoid heavy knocks or impact

• Remove jewellery during heavy work or manual activities

• Store opal pieces separately from harder gemstones• Clean gently with warm water, mild soap, and a soft cloth.

With proper care, opal jewellery can be enjoyed for many years.

Jewellery by Jack the Jeweller

At Jack the Jeweller, the focus is on creating jewellery that highlights the natural beauty and individuality of Australian opal.

Each piece is designed to showcase the unique character of the stone, ensuring that every item is truly one of a kind.

Whether you are searching for a meaningful gift or a piece to keep for a lifetime, opal jewellery offers something that no other gemstone can provide.