Salt and pepper diamonds

Salt and pepper diamonds have become a popular choice in engagement rings due to their uniqueness and are natural diamonds that are heavily included. Each one has distinctive markings, some resembling a pattern of stars in the night sky – these are called galaxy diamonds. These black markings are carbon spots, pieces of the diamond that never crystallised properly. Salt and pepper diamond engagement rings vary greatly in design as well as the shape of the centre stone, and can be anything from classic to asymmetric and non-traditional.


They are available in a number of shapes from the more traditional round, oval, cushion, pear and emerald cut, to the unusual, such as kite, hexagon, lozenge and freeform. Rose cut stones (ones that have a flat back and a faceted top) don’t provide as much light return or sparkle as the brilliant cut ones (with a traditional crown and a full pavilion), which scintillate similarly to their colourless counterparts and are more highly valued.


Presented in a variety of colours from white, grey, black to yellow, brown, champagne, blush and pink.


Diamond is the hardest-known mineral, and salt and pepper diamonds are no exception. However, salt and pepper diamonds need to be carefully selected, as much of the material can be poorly cut and contain cracks and chips.


Salt and pepper diamonds are technically lower in quality, as dictated by the four Cs (cut, colour, clarity, carat) of diamond evaluation. But if you find their uniqueness attractive, the good news is they are much more affordable than colourless diamonds.


Angola, Australia, Botswana, Namibia, Russia, South Africa, Zaire.

Major cutting centres of diamonds are in Antwerp, Bombay, New York, Tel Aviv.


Hardness: 10 Mohs

Specific Gravity: 3.417-3.55 (diamond)

Refractive Index: 2.417 -2.419

Crystal Form: Cubic. Diamond crystals occur well-shaped as octahedra, cubes, rhombic dodecahedral and macles. Diamond is found in igneous rock formations and alluvial deposits.

Treatments: None

Special Care: None

Durability: Very good

Lab grown diamond engagement rings

Lab grown diamonds have been used for industrial purposes since the 1950s and gradually made their way to the jewellery market. Nowadays, natural and lab grown diamonds coexist, accepted by both consumers and the trade. Lab grown diamond engagement rings have been gaining popularity due to their much lower cost and excellent colour, clarity and cut.

With identical looks, hardness and durability to the natural diamond, lab grown diamonds represent better value for money (costing on average 30-40% less than a natural diamond), with couples being able to afford a bigger, better quality stone to set into their engagement ring.
Lab grown diamond (also referred to as synthetic diamonds, man-made diamonds, laboratory-created diamond, or cultured diamonds) is a gemstone made of the same material as its natural counterpart: pure carbon, crystallised in an isotropic 3D form. Lab grown diamonds are not imitation diamonds, which are made of non-diamond material.

Man has attempted to synthesize diamonds since the late 19th century, however, the first reproducible synthesis of a diamond took place in 1950s in the Soviet Union, United States and Sweden, via the CVD (chemical vapour deposition) and HPHT (high-pressure high-temperature) methods. These two processes still dominate the production of lab grown diamonds today.

The only chemical difference between lab diamonds and natural diamonds is that
most natural diamonds contain tiny amounts of nitrogen, and lab diamonds do not. Of course there is more to a diamond than just its chemical structure. According to professionals with over 50 years of experience in diamond sales, there is energy that sort of speaks to you and can be felt the moment you hold a natural diamond in your hand. However, both lab grown and mined diamonds look identical, and only sophisticated technology can help tell the difference between a natural diamond and its synthetic counterpart.


Chemical Vapor Deposition (CVF) method where the diamond is grown from a
Type IIa natural diamond seed. These diamonds have the same chemical
composition and molecular structure as mined diamonds.

Type IIa is the rarest and purest type of natural diamond crystal that sparkles more
and shines brighter, with the least amount of impurities, especially nitrogen.

Less than 2% of all diamonds ever found in nature are Type IIa. Today, the CVF
method allows to buy a bigger, cleaner and Type IIa diamond for the same spend. Like mined diamonds, laboratory grown CVD Type IIa diamonds, have very few higher grade colours, D, E and F colours are very rare - like in nature, there is very little control over the colour.


High Temperature High Pressure (HTHP) method where the diamond is grown from a metal catalyst. HPHT diamonds are made using one of three manufacturing processes: a belt press, a cubic press, or a split-sphere (BARS) press. With HTHP lab grown diamonds, the colour is controlled, thus higher colours are readily available. Larger HTHP lab grown diamonds can contain a metal catalyst and sometimes even stick to a magnet.

The advent of synthetic gems on the market created major concerns in the diamond trading business, as a result of which special spectroscopic devices and techniques have been developed to distinguish synthetic and natural diamonds.


Lab grown diamonds generally cost 30-40% less than mined diamonds, but look
exactly the same. The price difference is for the most part due to the high costs involved in mining and removing tons of earth to find natural gem-quality diamonds.


Hardness: 10 Mohs
Specific Gravity: 3.417-3.55 (diamond)
Refractive Index: 2.417-2.419
Crystal Form: Cubic
Special Care: None
Durability: Very good

White diamonds: beyond the 4Cs


Beyond the 4Cs of white diamonds is a multitude of fascinating facts. Despite the fact that diamonds are made of carbon, there’s something almost supernatural about them. Just the word ‘diamond’ invokes luxury, desirability and toughness. Yet when we think of the element carbon we are more likely to think of charcoal: soft, black, opaque, earthy, lightweight. In contrast with carbon in its low pressure form as charcoal or graphite, carbon atoms in diamond are fixed together in a strong, three dimensional network. This leads to unique physical properties: diamond is a clear, extremely hard, often colourless mineral with a very high density.

Diamonds sparkle and have internal “fire” because of their very high refractive index. This means light is “caught” inside the crystal and re-reflected off the internal surfaces. Faces and facets made by gem cutters accentuate this property.

Diamond is the hardest known substance, the greatest conductor of heat, has the highest melting point of any substance (4090°C or 7362°F), and the highest refractive index of any natural mineral. Diamond measures 10 on the Mohs hardness scale, and is approximately 4 times harder than Corundum (sapphire and ruby), which is 9 on the Mohs scale.


Diamonds form deep within the earth under extreme heat and pressure.

Although diamonds have been prized as valuable gems for a long time, until the early 1700s virtually all traded diamonds came from river gravels (known as “alluvial deposits”) in India. Then in the early eighteenth century diamonds were discovered in Brazil, and from 1866 onwards were mined in South Africa. It was in this country that diamond’s major, violently erupted, volcanic source rock known as “kimberlite” was identified for the first time.

This recognition fundamentally changed the diamond exploration and mining industry, and quickly led to vastly increased production and to the high demand from the modern jewellery industry. Supply of diamonds to the market has long been tightly controlled by a small number of major producers – examples include De Beers (South Africa-Botswana), Al Rosa (Russia), Rio Tinto (Argyle Mine Australia and Canadian mines) and Lucara Diamond Corporation (Karowe Mine, Botswana), the Diavik kimberlite pipe in northern Canada.


Most diamonds are brown or yellow in colour. The jewellery industry has favoured colourless diamonds or those that have a colour so subtle that it is difficult to notice. Diamonds in vivid natural hues of red, orange, green, blue, pink, purple, violet or yellow form a group of Fancy Colour diamonds. They are extremely rare and valuable.


Diamond is the hardest-known mineral, measuring 10 on the Mohs hardness scale. However, the hardness of diamond is directional. It is hardest parallel to its octahedral planes and softest parallel to its cubic planes.


Unlike other mined commodities such as copper, gold, oil or coal, diamond has no spot market. Its value is variable and highly subjective, assessed using the 4Cs system: colour, clarity, cut and carat (5 carat = 1 gram). Per carat, uncut diamond values typically vary from around $US10 to $US3,000. Very large (sometimes very historical) gem-quality diamonds however may command price orders of magnitude beyond this. Until 1950s, there was no agreed-upon standard by which diamonds could be judged. GIA (Gemological Institute of America) created the first, and now globally accepted 4Cs standard for describing diamonds.



When talking about colour range in white diamonds what we are actually looking for is the absence of colour. A truly colourless diamond is extremely rare and highly prized. Most diamonds possess varying degrees of colour creating differences in value. The highest grade for a diamond with absolutely no colour is D and letter grades are assigned alphabetically all the way down to Z. An ‘icy white’ diamond is typically D, E or F. However, some people like the ‘warmth’ of an I, J or K colour. Within a given budget, you should seek the best balance of clarity, cut and carat to find the perfect diamond for you.


Diamond clarity is symbolic of ‘purity’ – the more flaws, the less valuable the diamond. Flawless, VVS (Very Very Slightly included), VS (Very Slightly included) and SI1 (Slightly Included 1) have the least inclusions or flaws. SI2 (Slightly Included 2) is borderline where inclusionsmay become visible to the naked eye. I (Included) rated diamonds have obvious inclusions or flaws visible to the naked eye.


Of all the 4Cs, cut has the greatest effect on a diamond’s beauty. Two diamonds of the same size, colour and clarity will look visibly different depending on their cut – one may look brilliant and bright, the other dull and drab. The better quality the cut the more brilliance and beauty the diamond will have.

Diamond cut grading runs from Excellent to Poor, with Excellent cut diamonds possessing correct proportions and an even pattern of bright and dark areas.

A diamond that is cut is too shallow, with an overly large spread for its carat weight will “leak” light through the sides or bottom of the stone, while a well-cut and proportioned diamond will reflect out the light through the crown, resulting in superior brightness, fire and scintillation.

Brightness is the measure of light reflected from a diamond.

Fire refers to the scattering of white light into all the colours of the rainbow.  Scintillation is the amount of sparkle that a diamond has, and reflections inside the diamond resulting in a particular pattern of dark and light areas.


Diamond carat is the standard used to measure diamond weight. A carat equals 1/5 of a gram. As diamonds increase in size, their cost tends to increase exponentially. Weight does not always enhance the value of a diamond – particularly if it is cut badly. Indeed a good cut can enhance the perceived size of a diamond.


Diamond fluorescence is the tendency for the stone to glow when it is subjected to ultraviolet rays from sources like the sun and fluorescent lamps. It looks like a bluish, a yellow or orangey hue. Once the ultraviolet light source is removed, the diamond stops fluorescing.

The element that creates this effect is boron and only about 30% of diamonds exhibit some degree of fluorescence. It grades from None, Faint, Medium to Strong and Very Strong.

Generally, the presence of fluorescence is undesirable, however if we compare two diamonds that have the same lower colour grade, the diamond that has blue fluorescence will have a whiter face-up appearance, as the blue hue helps mask a yellowish tint. Yellow fluorescent hue will enhance a yellowish colour of a lower colour grade diamond.


CIBJO The World Jewellery Confederation

CSA Jewellery Council of South Africa

DCLA Diamond Certification Laboratory of Australia

DPL Diamant PrufLabor, Germany

EGL European Gemmological Laboratory

GIA Gemological Institute of America

HRD Antwerp World Diamond Centre

IGI International Gemological Institute


When done by certification companies, laser inscriptions are taken as validation and proof of the quality of the diamond. Moreover, they help to avoid confusion, determine ownership, as well as deter fraud in the diamond industry.


Many diamonds contain inclusions of other minerals, which are captured samples from the deep Earth rocks in which the diamond grew. These provide important information for geologists. For example, inclusions of the minerals olivine, pyroxene and garnet tell us their host diamonds grew at depths between about 120 and 300km, in a layer of the Earth known as the sub-continental lithospheric mantle.

This layer is part of the Earth’s continental tectonic plates, and lies below the oldest regions of Earth’s continental crust known as “cratons”. Cratons are up to four billion years old – examples include the Australian Pilbara, the South African Kaapvaal, the Canadian Slave and the Russian Siberian craton.

The Pink Star is said to be the largest internally flawless fancy vivid pink diamond ever graded.


Although the sub-continental lithospheric mantle is the most common source of diamonds, some come from much deeper layers in the Earth. These are called sub-lithospheric diamonds, and identified by mineral inclusions consistent with being exposed to much higher pressures found at depths of more than 650km.

recent study looked at a type of rare blue diamond like the Hope Diamond. The researchers consistently detected very high pressure mineral inclusions indicating their diamond hosts grew at depths of at least 660km. These diamonds are blue because of the presence of trace amounts of the element boron.

The question of how boron ended up at great depths in the Earth’s mantle is a fascinating one. Boron is an element that on Earth is highly concentrated in the upper continental crust (less than 20km deep) and in ocean water. Its concentration in deeper mantle rocks is typically extremely low. Boron then must have been re-introduced to the deep layers where the diamonds grew.

This would likely have happened through a process called deep subduction, where the boundary of an oceanic tectonic plate (about 100km thick) fails, and the plate then collapses into the deep earth’s mantle. This moves boron and other materials from the shallow layers of the Earth down into depths of over 700 km.

Kimberlite eruptions then bring the diamonds up towards the surface.

Subduction of oceanic lithosphere with boron (B) captured from the oceans and delivered by the subducting oceanic slab to lower mantle depths in excess of 660km. Here the boron is supplied to the growing ultra-high pressure sub-lithospheric diamonds.


In addition to the boron example above, evidence from other diamond mine sites also supports the idea that Earth elements move from relatively shallow to deeper into the Earth through the process of subduction.

This has been detected by tracking different forms of carbon in diamonds from the South African Cullinan mine, and on mineral inclusions in South Australian diamonds.

Deep parts of the Earth still have a physical connection with layers closer to the surface. So yes diamonds are valuable due to being beautiful, hardy and relatively rare – but they also provide a fantastic window into the structure and the history of our Earth.


Angola, Australia, Botswana, Namibia, Russia, South Africa, Zaire. Major cutting centres of diamonds are in Antwerp, Bombay, New York, Tel Aviv.


Lab-grown or synthetic diamonds are a complete copy of a natural diamond that contain the same crystal lattice structure and chemical formula as a natural diamond.

To form a diamond crystal, the element carbon is placed under high pressure and the temperature of the surface of the Sun. Another way to form a synthetic diamond would be through a chemical vapour deposition where a small seed of a diamond crystal is grown layer by layer in a chamber.

Identification of a natural diamond from a synthetic diamond requires specialised equipment. The nature of inclusions in a natural diamond differs from the types of inclusions found in a synthetic diamond. Not all inclusions are easily visible through the naked eye or by using a loupe.

Lab grown diamonds are inscribed with letters “LG” at the base of the stone.


Cubic Zirconia, Moissanite, Swarovski Crystal.


Hardness: 10 Mohs

Specific Gravity: 3.417-3.55

Refractive Index: 2.417 -2.419

Crystal Form: Cubic. Diamond crystals occur well shaped as octahedra, cubes, rhombic dodecahedral and macles. Diamond is found in igneous rock formations and alluvial deposits.

Treatments: Annealing, Irradiation, High Pressure, High Temperature (HPHT), laser drilling, fracture filling, coating.

Special Care: None

Durability: Very good


Image and ring:

Australian Parti Sapphire in engagement rings

Sapphire love

Parti sapphires, including the beautiful gemstones from Australia, have been a firm favourite for couples looking for a unique coloured gem for their engagement ring, with gorgeous teal and blue green sapphires being the most popular choice. Sapphires of all colours belong to the corundum family of gems, that also includes ruby, and are a durable gem suitable for everyday wear pieces, such as engagement rings. We have been creating many Australian parti sapphire engagement rings for couples looking for a unique centre stone, as not two parti sapphires are alike. Parti sapphires typically display green, blue, teal and yellow colours, with some stones having more distinct, clearly defined colour zones, and others having more blended colours. These amazing gemstones look spectacular on their own or paired with diamonds, such as kite shaped, trillion, pear cut, baguette or round. Contemporary take on the classic three stone, or trilogy engagement ring design is on point right now (and we believe will stand the test of time), and parti sapphires look gorgeous highlighted by a sparkling diamond on each side.

Oval cut Australian Parti Sapphire 2.07ct, by Sydney jeweller Lizunova Fine Jewels, Chifley Square

Some parti sapphires display an enchanting blend of teal, blue, green and yellow colours, like this 2.07ct oval cut Australian parti sapphire. Image: Lizunova Fine Jewels

As a contemporary Sydney jeweller, we have been seeing a trend of couples moving away from the more traditional diamond as their engagement ring gemstone, and towards coloured gemstone alternatives, which offer more individuality, versatility and value for money. The striking Australian parti sapphires really stand out for their uniqueness and great value for money as a contemporary engagement ring centre stone choice.

Australia is blessed with some of the most unique and exotic gemstones in the world precious black and white opal, yellow and pinkdiamonds well as unique and stunning parti sapphires.

When you think of a sapphire, the colour bluemay immediately come to mind. However, thisincredible gemstone is found in a wide array of colours, varying from black to allshades of blue, to green, yellow, pink, white, orange, violet and purple. These colours, apart from red (known as ruby), blue or white, are referred to as fancy sapphires.


This cushion cut Australianparti sapphire displays a wonderful blend ofgreen, yellow and teal. Image: Lizunova Fine Jewels

Sapphire is a gem quality corundum that is hard wearing, measuring 9 on the Mohs hardness scale, making it an ideal alternative to diamond in a piece of jewellery worn every day, such as an engagement ring.

Parti sapphires are multi coloured stones that feature colour zones of two or more colours: predominantly blues and yellows - and sometimes greens. The stones are so striking as the colours contrast sometimes vividly, making them a delight for a jewellery designer. These gems are not seenin commercial, mass produced jewellery, where a manufacturer must bulk buy gems that are carefully matched in size, colour and shape. As each parti sapphire is unique, it makes the piece of jewellery, eg an engagement ring, unique to each couple.

Parti sapphiresare cut from sapphire crystals that display colour zones of two or more different colours, in such a way that the colours are accentuated and shown off in distinct colour zones, or blended into more even shades. The skill and artistry of the gem cutter is truly put to the test when it comes to cutting parti sapphires! They must first carefully examine the rough, to determine the best cut to transform it into a beautiful stone thatshows off its unique colour properties.

The gemstones display different colours when viewed from different angles and in different light sources, making them ideal for people who appreciate gems with personality and individuality.

Australian sapphires are from alkali-basalt related deposits and are very rich in iron content. Most of the stones are dark blue to bluish black due to the traces of iron. Due to varying concentrations of transition elements (e.g. iron and titanium) in the chemical make-up of the parent fluids (sapphire is essentially aluminium oxide) different colours result. The parti sapphires are so special as each stone has a unique combination of zoning and banding.


Zonesof teal, green and blue in this oval cut Australian parti sapphire. Image: Lizunova Fine Jewels

We love working with this beautiful, truly unique gemstone, especially, when it's selected for a bespoke engagement ring. We source a selection of sapphires for you to view in person, prior to making this important decision, and talk you through all aspects of the design process.

Check out our ready to wear parti sapphire engagement rings here, or book an appointment with us to view our selection of beautiful loose sapphires, and begin creating your bespoke engagement ring with one of these beauties.