Ahead of November, the story of topaz: a name borrowed from a Red Sea island that never produced it, centuries of legends, and the imperial topaz of tsarist Russia.
The Academy Museum says Taylor Swift will perform at its sixth annual gala on 17 October, closing a night honouring John Carpenter, Colman Domingo and Charlize Theron.
Couture from the Palais Galliera opens in Minneapolis and the Art Gallery of Ontario unveils Sunday Best, two major fashion exhibitions this October.
Made in 1849 for gamekeepers at Holkham Hall, the bowler went on to win the American West, the City of London and the Bolivian highlands.
Gucci's new High Jewellery turns flowers and rope into coloured gems, while India's jewellers prepare for a festive season shaped by high gold prices.
Blue sapphire's story takes in Persian legend, an 1881 landslide in Kashmir, a famous 1964 museum theft and one of the most copied engagement rings of all time.