A Guide to Gemstones

Nature’s Creation

Magical minerals created by Mother Earth. The beauty, durability and rarity of gemstones have enchanted humanity throughout history, and they have long been used in jewellery design, with the discovery of turquoise and lapis lazuli treasures dating all the way back to Ancient Egypt.

We use coloured gemstones throughout our jewellery, as a precious compliment to so many of our designs. From opals and blue sapphires in our 18ct gold Oceans Fine, to morganites, amethysts and aquamarines in our Forest Jewel rings.






Myths & Legends

The story of gemstones is an old one. ‘Jewels’ ranging from humble seashells to rough emeralds have been found in archeological sites dating back 20,000 years. It’s no surprise that the beauty of gems, their vibrant colours and unusual shapes have inspired civilisations to both imagine and believe all sorts of myths and legends throughout history. Rubies were once believed to cure poison, and aquamarines were once thought to calm the roughest of seas.

Picking the Right Type for You

Choosing your dream stone is an exciting and personal choice, but we would always recommend considering how your jewellery will be worn – for everyday wear we would suggest a relatively durable gemstone. Pearls have traditionally been a romantic choice for engagement jewellery, however they can be easily scratched by other materials. On the other hand, sapphires are highly resilient, making them a popular choice for those opting for colour in their wedding and engagement jewellery. The resistance of minerals is assessed using the Mohs Scale of Hardness. Materials appear on this scale ranging from 1-10 - for example, talcum powder is 1 and diamonds are 10.


Our Favourite Coloured Gemstones 


Sapphires are the second hardest mineral on Earth, making them a fantastically durable 9 on the Mohs scale. They also come in a rainbow of hues. Most commonly known in blue, sapphires also come in vibrant yellows, oranges, purples and pinks. Peach sapphires – known as Padparadscha are some of the most beautiful and rare. Unlike conventional sapphires, which can be of a lower quality and are often heat treated to intensify their colour and uniformity, the sapphires used in Alex Monroe fine jewellery are completely natural with a quality, freshness and complexity of colour unlike any other stone.

Our Sapphire Jewellery

Once believed to calm the oceans, Aquamarines are beloved for both their fresh, watery blue-green hue, and transparency. Aquamarines rate 7.5/8 on the Mohs scale, and with their subtle colour and a lustre that really sparkles, they are a popular alternative to white diamonds in engagement and wedding jewellery.

Our Aquamarine Jewellery

Morganites are known for their unique peachy-pink pastel colouring, produced by traces of manganese within their translucent crystal structure. They have a durable 7.5-8 rating on the Mohs scale, making them a practical choice for everyday wear. Tiny white diamonds are a perfect pairing with morganites, enhancing their sparkle, and rose gold beautifully brings out their colour.

Our Morganite Jewellery

Opals traditionally come from Australia, and are characterised by flashes of colour which appear from deep within the stone. This iridescent play of colour is caused by tiny spheres of amorphous silica, which naturally refract the light. Unlike other gemstones, opals are not crystalline, and are instead formed from hardened silica gel, which makes them both unusual and quite fragile. Measure 5.5 -6 on the Mohs scale, they can be affected by changes in temperature, humidity and light so must be stored and worn with care.

Our Opal Jewellery

Favoured by the Victorians, it’s most well known as a rich purple stone. However, at Alex Monroe we really love pale green amethyst, which is more unusual and looks stunning paired with yellow gold, and makes a wonderful statement cocktail ring, as seen in our Forest Jewel. A type of quartz, amethyst is a 7 on the Mohs scale, so needs to be cared for a little more gently.

Our Amethyst Jewellery

One of the most precious gemstones in existence, prized for their rich colour, rubies have been long favoured by royalty and were once believed to protect soldiers in battle. Ranging from a vibrant orangey-red to a more purple hue, they measure a resilient 9 on the Mohs scale, making them a practical choice for pieces worn every day.

Our Ruby Jewellery

Humans have long been enchanted by Emeralds, as one of the most vibrant and beautiful greens created by the natural world. These special stones are traditionally shaped into an ‘emerald’ cut, to emphasise their colour, which is prized far higher than their sparkle. Emeralds measure 7.5 -8 on the Mohs scale, which means they require a little more care than harder wearing stones.


The only gemstone in the world formed by a living organism, pearls are considered to be the world’s oldest precious stones, and were first discovered by early humans searching for food along the seashore. Known and loved for their iridescent sheen, pearls measure just 2.5 on the Mohs scale. A stunning choice for jewellery, as long as they are properly taken care of.

Our Pearl Jewellery

A rich and vibrant green garnet, often compared to an emerald with a little extra sparkle, Tsavorite is considered one of the world’s finest coloured gemstones, and was formed in Kenya and Tanzania, before the time of the dinosaurs. Tsavorites measure 7 - 7.5 on the Mohs scale, so whilst relatively durable, do require a little extra care.

Our Tsavorite Jewellery



Creating Your Own

Today, many people are veering towards unusual engagement rings, opting for creative styles that reflect their personality. Coloured gemstones are the perfect choice for engagement rings that make a statement and are a great way to express individual style. If you are looking for a bespoke ring, then there’s no better choice than a unique coloured gemstone – many of which are one of a kind!

Discover our Bespoke service