When Michelle Obama made headlines during a campaign fundraiser earlier this year, it was not because of anything she said or any go-team fist bumping she did but, rather, something she wore: a great big look-at-me necklace made of vintage crystals and pearls by jewellery designer Tom Binns.

In doing so, Mrs Obama provided final proof that a trend the jewellery world has been tracking for the past few years has reached critical mass.