High jewellery reveals its hidden gems, while 1960s Danish jeweller Griegst makes a comeback

The thing about real jewellery - by that I mean really expensive jewellery - is that you can't just take a pair of scissors to it like you might your old jeans when you want to switch it up a little (or a lot). But jewellery houses have always been keen to please their wealthy clients with jewels that transform in some way, and not just by selling tiaras that can be worn as necklaces.

Harry Winston's Secret Wonder necklace sports a central diamond-encrusted medallion that rotates to reveal an aquamarine- and sapphire-studded reverse, for when you feel you're wearing too many diamonds, while G by Glenn Spiro's Reveal ring twists to bloom open and show off its deep-green emerald-studded heart.

Mikimoto's new high-jewellery collection Jeux de Rubans includes a gorgeously oversized pearl and diamond bow, detachable from the necklace it rests on and wearable as a brooch, while Cartier's wine-stain-purple spinel and topaz brooch separates from the pearl bracelet to which it's attached.

But the greatest secret of all? The tiny golden cage containing an even tinier golden bird hidden inside the pearl tassel of Van Cleef & Arpels' Promesse de l'Envol necklace - a secret to keep all to yourself.

Golden boy

Late Danish artist and goldsmith Arje Griegst's jewels had the sort of ethereal, otherworldly quality that won him global recognition in the 1960s and beyond, and now Griegst's son Noam, a photographer, is reviving the brand using his father's original casts.

Copenhagen's It girls have been clamouring for a private viewing at the house's by-appointment-only showroom for a while now, but this month, Griegst will relaunch exclusively with Dover Street Market.

18ct-gold and diamond Spiral earring, ￡3,198, Dover Street Market 

Griegst perfected the lost-wax casting technique to extraordinary effect - think swirls of gold like a lock of Rapunzel's hair, gems sunk into seemingly molten metal, and faces morphing out of golden waves.

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