LONDON — The cameras had barely finished flashing on the newly engaged Prince Harry and Meghan Markle. But Emma Bridgewater, a British ceramics manufacturer, was already making a mug to commemorate the royal moment.

The next week, just under 1,000 mugs — with “Harry & Meghan are engaged,” and the date of the announcement on them — were on sale. They retailed online for around 20 pounds, or $27, and sold out within 24 hours.

From crockery emblazoned with official portraits to solar-powered toys with the queen’s characteristic wave, Britain’s monarchy is big business. And that royal economy, normally catering to tourists and enthusiasts, kicks into high gear around major events.

“It’s a flash of color in a rather gray world,” said Emma Bridgewater, the eponymous founder of the ceramics company.