A Guide to Natural Gemstones

Diamonds may be the traditional choice for fine jewellery, but the world of natural gemstones offers an extraordinary spectrum of colour, character and individuality.

From the deep blue of sapphire and vivid red of ruby to the unmistakable green of emerald, every natural gemstone has its own story. Formed within the earth over millions of years, natural gemstones are prized not only for their beauty, but also for their rarity and uniqueness.

At Dream Diamonds, we source natural gemstones for engagement rings, special occasion jewellery and one-of-a-kind custom-made pieces. Understanding the differences between gemstones can help you choose a stone that suits both your personal style and the way the jewellery will be worn.

Precious Gemstones

Traditionally, diamonds, rubies, sapphires and emeralds have been referred to as the four precious gemstones. The term reflects their historical rarity, desirability and importance in fine jewellery.

Today, however, there are many other exceptional natural gemstones worthy of consideration, including aquamarine, tourmaline, tanzanite, spinel, morganite, garnet and amethyst.

Each gemstone differs in colour, rarity, durability and value.

Sapphire

Although blue is the colour most commonly associated with sapphire, natural sapphires occur in an impressive range of colours including pink, yellow, green, purple, orange and colourless.

Sapphire is a variety of the mineral corundum and measures 9 on the Mohs hardness scale, making it one of the hardest natural gemstones and an excellent choice for jewellery designed to be worn regularly.

Fine sapphires are valued according to factors including colour, clarity, cut, size, origin and whether the gemstone has undergone treatment.

Ruby

Ruby is also a variety of corundum and shares sapphire's excellent hardness of 9 on the Mohs scale.

It is the presence of chromium that produces ruby's distinctive red colour. The most desirable rubies can display an intense, vibrant red, although natural rubies occur in a range of red tones.

Fine-quality natural rubies, particularly in larger sizes, can be exceptionally rare and valuable.

As with sapphires, colour, clarity, cut, carat weight, origin and treatment can all influence the value of a ruby.

Emerald

Emerald is famous for its rich green colour and has been treasured for thousands of years.

Unlike diamonds, rubies and sapphires, natural emeralds commonly contain visible internal characteristics. These inclusions are often collectively referred to as the gemstone's jardin, from the French word for "garden".

Rather than automatically making an emerald undesirable, these natural characteristics can form part of its individual appearance and provide evidence of its natural formation.

Emerald measures approximately 7.5–8 on the Mohs hardness scale. While reasonably hard, emeralds can be more susceptible to chipping and require greater care than diamonds, rubies or sapphires.

Other Natural Gemstones

Beyond ruby, sapphire and emerald is an enormous variety of beautiful natural gemstones.

Aquamarine is admired for its delicate blue to blue-green colour and is part of the beryl family, the same mineral family as emerald.

Tourmaline occurs in an extraordinary range of colours, including green, pink, red and combinations of multiple colours within a single gemstone.

Tanzanite is known for its distinctive blue-violet colour and is found commercially in only one small area of Tanzania.

Spinel occurs naturally in numerous colours and has historically been mistaken for ruby. Fine red, pink and blue spinels can be particularly beautiful.

Morganite is another member of the beryl family and is recognised for its soft pink to peach tones.

Amethyst is the purple variety of quartz and can range from pale lilac through to deep violet.

Natural Characteristics and Inclusions

One of the fascinating qualities of natural gemstones is that no two stones are exactly alike.

Many gemstones contain inclusions, colour zoning or other internal characteristics created during their formation within the earth. The type and visibility of these characteristics vary considerably between different gemstone varieties.

For this reason, gemstones should not always be judged by the same standards used for diamonds.

With coloured gemstones, colour is often one of the most important considerations.

Treatments

Treatments are common within the natural gemstone industry and can be used to improve a gemstone's colour or appearance.

For example, heat treatment is widely used for sapphires and rubies, while many emeralds are treated with oils or similar substances to reduce the visibility of surface-reaching fractures.

A treated gemstone can still be a natural gemstone. However, the type and extent of treatment can have an important effect on rarity and value.

For significant gemstones, independent laboratory certification can help identify whether a gemstone is natural and whether detectable treatments are present.

Choosing a Natural Gemstone

There is no single "best" gemstone.

The right choice depends on the colour you love, the style of jewellery, your budget and how frequently you intend to wear the piece.

For an engagement ring or jewellery intended for everyday wear, durability becomes particularly important. Sapphire and ruby are excellent choices because of their hardness, while emerald and some other gemstones require a little more care.

For occasional jewellery, the possibilities become considerably broader.

Creating Something Unique

Natural gemstones provide an opportunity to create jewellery that is genuinely personal.

Whether you are looking for a classic blue sapphire, a vivid ruby, an exceptional emerald or something completely different, Dream Diamonds can source individual natural gemstones and design a piece of jewellery around the stone you select.

With more than 40 years of experience in diamonds, gemstones and jewellery manufacturing, we can guide you through the selection process and create a piece specifically for you.

Choose the gemstone. Choose the design. We'll create the jewellery around you.