From a maelstrom of heat and pressure, rock and minerals at the Earth’s crust deliver one of nature’s most astonishing prizes – the gemstone. From ocean-coloured sapphires, garnets in red or tsavorite green, lime peridots, kaleidoscopic tourmalines and iridescent opals to leaf-green emeralds, silky malachite, black onyx, rubies and honeyed citrines, fine jewellers today have a veritable rainbow of mineral crystals to choose from. Lest we forget the diamond. This long sought-for stone is graded on its clarity, flawlessness and colour – or more specifically, lack thereof, since diamonds with the least colour are the most prized, allowing light to pass through them and enabling a more brilliant sparkle.

The mining of virgin materials can have a huge impact on environmental, social and humanitarian welfare and since precious metals are defined by their enduring malleability, they make for a perfect recyclable material. Melted down and extracted from any other mixed metal, gold, silver and platinum can be recovered in their purest form again and again. Look to Spinelli Kilcollin’s Serpens Silver Bracelet for a powerful example of recycled metal use.

Gold and silver are naturally occurring metals that have formed the basis of global currencies since as early as 650 BC. Durable, ductile (meaning malleable enough to be formed and reformed into thin wire without losing toughness) and with a high lustre, the hardiness of these metals ensures their value – as does their finite availability on the planet. Gold in its raw state is incredibly soft; for everyday use it is mixed with other metals such as copper or silver depending on the desired hue of yellow, rose or white. The karat weighting identifies the mix: 18-karat gold has a higher percentage of pure gold (75 per cent) than nine-karat gold (37.5 per cent). While this differential technically makes nine-karat gold harder than 18, it is also more brittle – and thus less resilient to micro scratches. The highly resistant silver-white platinum, meanwhile, is one of the least reactive metals available, making it the ultimate heirloom material.

Advanced technology means that laboratories can now mimic the same conditions of heat and pressure under which diamonds and other gemstones naturally occur within the Earth’s mantle. Lab-grown diamonds are chemically indistinguishable from mined diamonds, containing only carbon atoms bonded to each other in a three-sided pyramidal structure. To the eye, the differences between the two are undetectable but to the planet, the difference is increasingly important. For his Mini Rose Garden 9-Karat Gold Sapphire Signet Ring, jewellery designer Mr Bleue Burnham arranged these lab-created sapphires in a design echoing the foliage in a rose garden.

Many pieces of jewellery are cast with empty grooves or channels, ready to be filled either with gems or other stones – perhaps turquoise or lapis – or filled with another liquid material such as enamel, and baked in. Jacquie Aiche’s mesmerising Gold, Opal, Enamel and Diamond Ring takes inlay to stratospheric heights.

Casting – the process of pouring a liquid metal into a cavity – dates back to 4,000 BC. Lost-wax casting is a common method: a design, often hand-carved from wax in the case of fine jewellery, is packed in a flask that is then filled with plaster. Upon high-heat treatment the wax will melt, leaving a carefully detailed depression; this space will then be filled with molten metal, becoming the final piece of jewellery once set. Hand-casting is a highly skilled technique employed in fine jewellery, too, where a piece of gold is cut and manipulated by hand – bending, rolling, shaping and hammering – to produce the finished object. See Laud’s expertly designed 18-karat Gold Bracelet for such precision.

Gem setting is an art in and of itself, designed to showcase the particular gemstone in its grasp. Bezel setting is where a custom-made strip of metal frames the stone, while pavé setting (a favourite in the sculptural pieces from Repossi) sees a series of stones clasped in a U or V-shaped frame that reveals the sides of the stones and enhances sparkle. Open settings prioritise light flow through the sides of a large stone – on an engagement ring setting, for example – while in the case of Healers Fine Jewellery it allows the crystal to touch the skin and thus transfer its properties to the wearer.

In fine jewellery, carefully cast links are often joined by hand, one by one, to create a chain. Whether the chain in question is delicate, elaborate or colossal in scale and style, this process is time-consuming and requires enormous skill. The best jewellery designers have honed their skills to the point that they are able to take an experimental approach, such as in the case of OLE LYNGGAARD COPENHAGEN, whose Love chains are composed of a series of irregular links, or mother-daughter design duo SHAY, whose gemstone and diamond-encrusted Cuban link bracelets combine the skills of link-making and gem setting to spectacular effect.

These are flaws found within the structure of both natural and lab-created diamonds, as opposed to “blemishes”, which are found on the surface of the diamond. Diamonds are graded on a scale of flawlessness, from barely visible to visible inclusions.

Not to be confused with karat – referring only to the weight of pure gold – a carat refers to diamond weight. One carat is equivalent to 0.2 grams. The higher the carat, the larger the visual size of the diamond and the rarer and pricier it is.

Traditionally known as the “gentleman’s ring”, the signet ring was once seen as a symbol of family heritage – today it is a gender fluid piece of jewellery with a raised or flattened platform decorated with an engraving or inlay that displays a personal representative of the wearer.