A s you fly into Pantelleria at the height of summer, what hits you first is the temperature: at 40C, it is the sort of shimmering, dry, dense heat that creates visual distortions on the horizon, without the dusty bluster of a sirocco to relieve it. Then you see scrub, yellowing grass, relative flatness and, last, outcrops of black, black rock.

Pantelleria is the strange, silent, volcanic island, midway between Sicily and Africa, to which Giorgio Armani repairs every August. “It is the only place where I truly feel I can turn off from the stress of working life,” says the designer, who first visited the island 35 years ago. “My sister says my face changes here. I turn off the spotlight, and my eyes are always focused on the clear sky.”

And it is Pantelleria, with its geologically unique formations of obsidian, that has inspired his new, mineral-rich skincare. Giovanni Orsi, a professor of vulcanology and geophysics expert, says: “Pantelleria is the black pearl of the Mediterranean.” He has been studying the island, Italy’s fourth largest, for more than three decades; the oldest rocks here date back 300,000 years.

Obsidian, which is as glossy and black as Japanese lacquerware, has special properties. It is formed from the same magma as the grey and porous pumice stone. The magma cools so quickly that the obsidian does not have time to form crystals; the resulting “glass” breaks easily into sharp, brittle pieces. Historically, it has been used as currency, and to make arrowheads and knives. Obsidian is alkaline, with high levels of sodium and potassium – minerals that make the soil extremely fertile – and the Pantescans, as the local population is known, have a long history of cultivating crops such as grapes, olives and capers. Those two minerals are also essential for human life and can improve the health of the skin; together with five other vital elements, including calcium and magnesium, they form the basis of Armani’s new moisturiser, Crema Nera.

Mineral skincare has been a growing trend for several years – Aveda’s Tourmaline was one of the first – and now there is a wealth of gemstone- and mineral-based creams available. But, while much of the new skincare is increasingly light, Crema Nera has a curiously solid, balm-like texture – quite a brave move. And I like it. Once smoothed onto the skin, the dense cream seems to dissolve magically and become an invisible film.

The notion of a universal cream – one that is suitable for all ages and skin types – is also radical, flying in the face of the specialisation that currently drives the skincare market. And, refreshingly, there are no great claims for it – although, yes, it firms; yes, it hydrates; and, yes, it nourishes. “Cosmetics are about enhancing rather than masking a woman’s features,” Armani says. Stylish simplicity – it’s his mantra.

This sense of back to basics, of communing with the elements, of paring life down to its most essential constituents, seeps into my mind as we drive around Pantelleria. The island has a roughhewn, organic beauty, unlike the Aeolian islands north of Sicily, more traditionally picturesque with their clusters of whitewashed villages, ports and vertiginous volcanoes. There’s a danger, a cruelty even, about the craggy shoreline, that brings to mind the Cornish coast of Daphne du Maurier or Emily Brontë’s Yorkshire moors.

About 90% of visitors to the island are Italian, many from the industrialised north. Some, like Armani, have bought one of the traditional Arabic domed, single-storey dammusi, to holiday here in August. We pass Armani’s compound – a coastal expanse boasting four or five renovated dammusi and a vast infinity pool – in the village of Gadir, which got its Arabic name during four centuries of occupation.

Weeks later, I’m back in my own bathroom, testing a little pot of Crema Nera. The lucent black packaging is a good approximation of the obsidian pantellerite rock. In an odd, abrasive, untamed way, this island has beguiled me, too. I will definitely go back. In the meantime, the skincare is an effective and pleasurable memento.

Crema Nera starts at £175. The Crema Nera range of cleansing balm, foaming cleanser and soothing lotion starts at £50. From Giorgio Armani counters nationwide

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