Key Takeaways Signet achieved 3% same-store sales growth in 3Q26, with its three largest brands posting 6% comps.Lab-grown diamonds now account for about 15% of fashion jewelry sales, nearly doubling from last year.A higher mix of LGD fashion helped lift AUR and drove 80 basis points of merchandise margin expansion.Lab-grown diamonds are rapidly reshaping the fashion jewelry landscape and Signet Jewelers Limited (SIG) is emerging as a clear beneficiary of this structural shift. The company is seeing strong ...