Online Jewellery Expert

A family history of over 200 years

Online Jewellery Expert

With a family history of over 200 years, we have an unrivalled experience in delivering jewellery excellence. We have forged unique relationships with diamond and gemstone dealers globally, which affords us the opportunity to bring not only the best quality diamonds and gems to you at very competitive prices, but also quality and value assurance is always guaranteed.

Jewellery and Gemstones Expertise available Online and in Person

Selecting your jewellery requires some very careful guidance, something we provide as standard here at Jonathan Lambert. If you’re seeking information about gemstones online, our Online Jewellery Expert section offers some useful tips and information. If your question is not answered here, then please contact us and Jonathan or Yasmin will be in touch.

 Buying Diamonds

When buying diamonds it is best to be guided by 4 C’s – Colour, Cut, Clarity and Carat


Diamonds are sold by the carat (shown as ct.), which is actually a unit of weight, though most think of a carat in terms of size. The word “carat” comes from the “carob” seed, the original unit of measure for diamond traders. Today, a carat is equal to exactly 0.2 grams (about the weight of a paper clip).


The cut of a diamond is often considered to be the most important attribute. Even diamonds with perfect colour and clarity can lose brilliance if cut poorly. A well proportioned diamond will have each facet properly placed and angled so as to maximize the amount of light that reflects back out of the crown (top) of the diamond, to the eye of the observer. This reflected light is perceived as fire and brilliance.


The colour scale of a diamond illustrates the difference in colour of diamonds. The alphabetical scale is graded from ‘D’ at the top of the scale which is the whitest, diamond grade to ‘Z’, which is very brown.

Diamonds come in a variety of colours, some of them highly prized (pinks, blues, even yellow). However in a white diamond, the presence of an obvious yellow tint will lower the price of a diamond. The less body color in a white diamond, the more true color it will reflect, and thus the greater its value.


Diamonds are formed deep within the earth under extreme heat and pressure. Virtually all diamonds contain “birthmarks”; small imperfections inside the diamond called inclusions. Clarity refers to the degree to which these imperfections are present. Diamonds which contain numerous or significant inclusions or blemishes have less brilliance because the flaws interfere with the path of light through the diamond.The scale of diamond clarity runs from FL Flawless to I3 inclusions visible to the naked eye.





Silver was once called the ‘lunar’ metal – its appearance being cold and luminous, similar to the moon’s reflection on water. It has always been a valuable metal, ever since it was discovered and first mined in Anatolia (now Turkey), more than 6,000 years ago. Classed as a ‘Noble’ metal, silver has a stable chemical structure that resists oxidisation and corrosion from acids.

Sterling silver is an alloy – 92.5% fine silver and 7.5% copper. Copper is added to fine silver so that it becomes more workable and durable, whilst retaining all of its beauty.


Gold has been mined since before 4000 BC. There are many different countries that have produced high levels of gold. Gold has always been and still is a rare metal.

Pure gold 24 karat is a very soft metal and not ideal for jewellery, Gold is therefore normally alloyed with other metals such as zinc, nickel, silver and copper to add hardness. The purity of gold is measured in carats which measures the gold content as part of 1000, with 24 karat gold being 100% pure, 18 karat gold 75% pure, 14 karat gold 58.3% pure and 9 karat gold 37.5% pure.

Gold’s price fluctuates every day and is bought and sold as a commodity. In times of economic uncertainty, the price of gold (and all precious metals for that matter) tends to become higher as gold is through of as a safe haven for money.

Gold is a very inert metal and this means that it won’t tarnish (i.e. react with the atmosphere) like silver, and therefore maintains its wonderful yellow colour. Gold is mined in South Africa and the United States. The chemical symbol of gold is ‘au’ from the Latin aurum, which means shining dawn. This relates to the exquisite and uniquely warm, yellow glow radiated by gold – an attribute that has helped make it the most desirable precious metal ever known to man.

White Gold

White gold has all the same properties as yellow gold but has been carefully alloyed with a mix of naturally white metals like palladium to give it a stunning white sheen.


Platinum, is the most hard wearing and expensive of all the precious metals. It is a very strong metal which makes it ideal to set precious stones with, and it’s expense is attributed to the fact that it is a rare metal.

Conflict Free Diamonds

Jonathan Lambert always only sources diamonds that are conflict free from suppliers who are signed up to the Kimberley Process

Our diamonds have been purchased from legitimate sources not involved in the funding of conflict and in conformance with United Nations resolutions.

Gemstone Guide

There are a fabulous array of coloured gemstomes available to use as a feature in an item of jewellery, whether this is one that you purchase or one that you have made.

All gemstones have a certain level of hardness and this is defined by the Mohs scale. The Mohs scale of mineral hardness is a scale which characterizes the scratch resistance of various minerals through the ability of a harder material to scratch a softer material. It was created in 1812 by the German geologist and mineralogist Friedrich Mohs.

The range can be a little overwhelming to say the least, so here is a guide which we hope will help you in making your choice.

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January birthstone

Legend has it that Noah suspended garnet in the ark to disperse light, and it has been said to cure melancholy and warm the heart. Generally a dark warm red stone but is available in a variety of colours.

7 – 7.5 on the Mohs scale of hardness
Mined from many sources around the world

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February birthstone

The name comes from Ancient Greek word ‘methystos” meaning intoxicated. Which refers to a belief that the stone protected its owner from drunkenness. The ancient Greeks made drinking vessels decorated with the stones in the belief that it would prevent drunkenness. Typically a purple colour ranging from very light purple to an intense deep purple.

7 on the Mohs scale of hardness
From the Quartz family
Mined from many sources around the world

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March birthstone

The name Aquamarine comes from the Latin ‘Aquamarina’ meaning water of the sea, which relates to its wonderful watery blue colour. Typically a very pale blue named after the sea.

7.5 – 8 on the Mohs scale of hardness
From the Beryl family
Mined from many sources around the world including Russia and America

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May Birthstone

Most emeralds used in historical jewellery would have been mined from Cleopatra’s mines in Egypt. These mines now only produce poor quality emeralds. Emeralds are also said to be the symbol of love and sincerity which may explain why the gift of an emerald is so popular for anniversaries.

7 on the Mohs scale of hardness
From the beryl family
Mined in Australia and Columbia

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June birthstone

Perhaps the best-loved gems of all time, pearls—natural and cultured—occur in a wide variety of colours. The most familiar are white and cream, but the palette of colours extends to every hue. The La Peregrine pearl is one of the largest and most famous pearls in the world. Adorned by actress Elizabeth Taylor, in 2011 it sold for $11.8. Available in a variety of colours including white, black, grey, yellow, orange, pink, lavender, blue and green.

2.5 – 3 on the Mohs scale of hardness
From Australia, China and The Philippines

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July birthstone

With its hardness and durability, it is a perfect engagement gem. And if worn on the left hand, ancient lore has it that the Ruby will bring good fortune to its wearer too. A red stone, available in shades of pink to dark red

9 on the Mohs scale of hardness
From the corundum family
Mined in Sri Lanka, Madagascar, Australia and Thailand among others

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August birthstone

Found in lava, meteorites, and deep in the earth’s mantle, yellow-green peridot is the extreme gem.

The ancient Egyptians mined peridot on the Red Sea island of Zabargad, the source for many large fine peridots in the world’s museums. In 2005, peridot was found in comet dust brought back from the Stardust robotic space probe.

6.5 – 7 on the Mohs scale of hardness
From the mineral Olivine
Mined in the USA, China and Pakistan among others

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September birthstone

Sapphire has long symbolized truth, sincerity and faithfulness. Because sapphires represent diving favour they were the gemstone of choice for Kings, consequently the British Crown jewels feature many sapphires. Generally seen in blue colour, but can also be pink, green, yellow, clear and other colours.

9 on the Mohs scale of hardness
From the corundum family
Mined in Sri Lanka, Madagascar and Thailand and other sources around the world

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October birthstone

Fireworks. Jellyfish. Galaxies. Lightning. Opal’s shifting play of kaleidoscopic colors is unlike any other gem. Because Opals have the colours of other gems the Romans considered it to be the most powerful of all gemstones.

Five main types of Opal include, white or light opal, black opal, Fire opal also known as ‘Mexican opal’, boulder opal where fragments of the surrounding rock called matrix, become part of the finished gem, and crystal or water opal which shows exceptional play-of-colour.

5 – 6.5 on the Mohs scale of hardness
Mined in Australia, USA, Peru and Brazil

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November birthstone

Citrine is recognized as one of the most popular and frequently purchased yellow gemstones. In the days before modern gemology, its tawny colour caused it to be confused with topaz. A trace of iron in citrine’s structure is responsible for its yellow-to-orange colour.

Mined in Brazil and Bolivia
From the mineral Quartz
7 on the Mohs scale of hardness

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December birthstone

The name Topaz is thought to be derived from the Sanskrit tapas meaning fire. The largest Topaz is in the Portuguese crown, and for many years was thought to be a diamond. It was given the name The Braganza Diamond weighing 1,640 carats. Mainly found in blue but also in pink, yellow and brown.

8 on the Mohs scale of hardness
Mined in Brazil, Sri Lanka, USA, Tasmania, and Mexico

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