London is one of the world’s most compelling cities for engagement-ring shopping, whether you are looking for a competitively priced certified diamond, a completely bespoke design, or a heritage piece from a storied British jeweller. The city’s jewellery scene ranges from the diamond specialists of Hatton Garden to the private showrooms of Mayfair and the independent designers of East London. For the best experience, plan your shopping by neighbourhood rather than visiting jewellers at random. Hatton Garden is ideal for comparing several specialists in one afternoon, while Mayfair suits buyers looking for a more polished luxury experience. Covent Garden and Shoreditch are better suited to contemporary and design-led rings. Where…