Pandora A/S rose the most in almost six months after the jewellery brand lifted its revenue guidance for this year, thanks to growing sales of lab-grown diamonds.

The Danish company, which makes more pieces of jewellery than any other in the world, said organic sales are projected to rise 8-10 percent this year, up from the 6-9 percent previously expected.

The shares advanced as much as 6.6 percent in Copenhagen, for the biggest intraday rise since Nov. 8. The shares are up more than 80 percent in the past 12 months.

Pandora’s first-quarter results confirm the business is in strong shape, analysts at Jefferies in a research note.

Sales of lab-grown diamonds surged 87 percent in the first quarter, the company said. Gross margins reached a record 79 percent, boosted by higher prices and the benefits from silver pricing and favourable foreign exchange rates.

While jewellery markets generally remain subdued, the company’s ongoing brand investments have allowed it to take market share, said CEO Alexander Lacik in the earnings release.

Pandora has previously said it’s targeting more than 1 billion kroner ($143 million) in revenue in the lab-grown diamond segment by 2026.

By Sabah Meddings

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