In the realm of high jewellery, there are diamonds, precious stones, and ornamental stones. But occasionally, unconventional materials come into play. Jewellery houses sometimes employ these to unveil their beauty or to stamp their unique creative identity.
An "unconventional" material in jewellery is defined by several aspects: either it’s found in small quantities, or it’s simply not valued. It might also be characterised by its difficulty to be worked and shaped, as is the case for some rocks that are too brittle. Others face challenges in sourcing, and some are restricted by regulations prohibiting their use — elephant ivory for instance, which is scarcely replaced by warthog ivory for sculpted pieces. Here’s a non-exhaustive list guided by the research of jewellery lecturer and consultant Marie Chabrol.
Ornamental Stones. The Great Come Back
Opals, rhodochrosites, chrysoprases, agates, malachites, rhodonites, sugilites, lapis lazulis… Very colourful, opaque, and often unfaceted, these ornamental stones are often seen as less "precious" than rubies, sapphires, and other emeralds. Trendy in the 70s, they had been forgotten for several years. It was not until 2016 that major jewellery houses reintroduced them through their collections, from Van Cleef & Arpels to Chaumet, including Fred, Cartier or Boucheron. Today, independent designers also use them, for a graphical, colourful rendering, and new ways of channeling their creativity.
Quartz with Inclusions. Remarkable transparency
Quartz has long been used in jewellery and actually encompasses stones with quite different aspects, whether opaque or transparent, such as rose quartz, citrine, amethyst, agate, or even jasper. Quartz with inclusions, on the other hand, encases various materials that can be solid, liquid, or gaseous, and is preferred perfectly colourless with crystals enclosed. Here, Marie Chabrol specifies: "These stones are found in quantity, but it’s a matter of finding enough of good quality so they can be used in high jewellery." The unique aspect of the inclusions can also pose problems when marketing the stones in series and therefore in searching for sufficiently uniform characteristics…
Marketed as "pebbles", river pebbles are sometimes used in high jewellery, their dark grey, very opaque and thick aspect contrasting with the delicacy of other precious stones or the refinement of the jewellery design. Maison Adler notably created the Pebbles collection, associated with pastel coloured sapphires, evoking the raw object, but without directly employing it in the creation of its pieces. In 2020 however, Paolo Spalla, an Italian jeweller, proposed a ring set with a diamond, placed side by side with a pebble mounted on the ring. Taffin Jewelry also sometimes crafts its jewellery with this material. But the use of pebbles remains quite rare among jewellers, who more willingly work with nobler and softer materials.
Maligano Jasper. Recent discovery
Brecciated jasper is a red stone possessing brown and black inclusions. Maligano jasper, discovered in 2011 in Indonesia on the island of Sulawesi, is a variety of brecciated jasper composed of different types of jaspers formed in ancient volcanic hot springs. Grey agate veins fill the breaches for a very singular rendering, unique to each stone, composed of a multitude of inclusions. Much like quartz with inclusions, its unique aspect makes Maligano jasper a difficult stone to use for the jewellery industry. It is thus still very little present on the market, but could well offer great creative possibilities to jewellers who would seize it.
Peanut Obsidian. Speckled
While the use of obsidian, a volcanic rock that is sometimes grey, dark green, red or black, is not rare in high jewellery, that of so-called "peanut" obsidian is much less frequent. Named after the small red or brown spots resembling peanuts that appear on its surface, this stone can be found in Mexico, the United States, Italy, or Greece. Yet, it is very rarely worked by jewellery houses.
Pine Cone. Petrified wood
In Patagonia, the Cerro Cuadrado Petrified Forest was buried under volcanic ashes about 160 million years ago. Transformed into rock, the ash partially preserved its ecosystem, including now fossilised Araucaria nuts. During their silicification, rhodochrosite grafted onto them, giving a pink hue to the pine cones. Maison Cartier presented a necklace adorned with a pine cone selected with care a few years ago. But the random dimension of these successive transformations can pose difficulties in exploiting these woods transformed into rock: it is necessary to find beautiful fossilised subjects, which should display a clear mix between silica and rhodochrosite. Some rather limiting factors, despite the exceptional character of these objects.
Indian Paint Rock. Drying up
Coming from Death Valley in California, the Indian paint rock mine is a sedimentary rock, formed by the accumulation of sediments deposited by water or air. Its black and ochre colours display patterns created by traces of iron and manganese, sucked into the rock through tiny cracks. With a satin rather than shiny polish, the stone offers a spectacular aesthetic aspect. The source of this material has however dried up and is no longer exploitable today.
Bubble Magnesite. Fragile
Bubble magnesite is a stone rarely used in high jewellery. As its name suggests, it has spots on its dark surface, like so many little orange bubbles. Like its cousin, the Wild Horse magnesite, white and traversed by small brown or grey lines, its cut is made difficult by its fragility. It is little used in large quantities, as it first needs to be stabilised — usually with a resin. It however sometimes appears in costume jewellery, or in cabochon form.
From a mineralogical standpoint, lepidolite is a fairly common stone, with deposits found in Brazil, Madagascar, India, the United States, or Zimbabwe. Much like Bubble magnesite, it is fragile and needs to be necessarily stabilised to be used in jewellery due to its friable nature, flaking when cut. It mainly appears in lithotherapy jewellery, being less sturdy or durable, and of poor quality. In the luxury industry, it is more so used in watchmaking to produce watch dials for instance, rather than setting jewellery.
Insects. Natural objects
Gilbert Albert, Swiss jeweller born in 1930 and passed away in 2019, is the go-to craftsman for unconventional and organic materials. His jewellery is adorned with sea urchin skeletons, shark teeth, or feathers, but also beetles or seashells. However, his preservation technique for exoskeletons remains unknown, and the use of such elements is difficult to develop and apply in series for jewellers — beyond obvious ethical considerations. High jewellery will prefer to use more traditional materials to represent nature — insects, flowers, or butterflies — in more durable and easily preserved materials.