U.S. jewelry retailers continued to post sales gains in September despite weakening consumer sentiment and broader concerns about the economy, according to monthly data from the Tenoris analytics firm.

Tenoris analyst Edahn Golan reported Oct. 7 that revenue at U.S. specialty jewelers increased 5.7% year over year in September, marking nearly two years of uninterrupted monthly growth. Year to date, specialty jewelry revenue is up 8.5%.

Golan’s data suggests, however, that the industry’s growth remains increasingly concentrated at higher price points. He reported that average spending per item rose 11% in September, while unit demand continued to weaken, particularly for lower-priced merchandise.

Sales of lower-priced jewelry declined 11% at specialty jewelers, even as revenue continued to rise.

Diamond sales followed a similar pattern. After an extended growth streak, sales of finished diamond jewelry slipped 0.6% in September, while total natural-diamond jewelry sales, including loose stones, declined 1%. At the same time, consumers who purchased diamond jewelry spent more, with average spending per stone increasing 11%, Golan said.

Lab-grown diamond jewelry continued to outperform natural stones, with demand rising nearly 26% year over year. However, revenue from loose lab-grown diamonds declined for the fifth consecutive month as falling prices continued to weigh on sales despite growing unit demand.

Tenoris’ data from jewelry stores stood in contrast to broader luxury spending trends. Reuters reported Oct. 6 that an analysis of credit card data by Citi found that U.S. luxury purchases fell 6% in September following 4% declines in both July and August. Citi said spending on watches and luxury jewelry weakened further during the month, although demand from affluent consumers remained relatively resilient.

Taken together, the reports suggest that while jewelry sales remain healthier than many other luxury categories, growth is increasingly dependent on a smaller pool of consumers purchasing higher-priced merchandise. Golan described the trend as revenue gains masking softer unit demand, making inventory planning and pricing strategy more important for retailers.

“Whether described as a K-shaped economy, market bifurcation, or a shift in the composition of consumer spending, the data point to a jewelry market increasingly divided by price point,” Golan said.