The amount consumers are shelling out on natural diamonds has increased over the past two years, as has the average size they are buying, according to a new report from De Beers.

Women in the US spent an average of $4,063 on a natural diamond in 2025, according to the miner’s most recent Diamond Report, which it released Tuesday. That’s a rise of 25% from $3,242 in 2023, the last time the company performed the study. Meanwhile, the average price of a lab-grown diamond was $2,786 in 2025. The average size per natural stone grew to 1.86 carats from 1.65 carats two years ago.

The overall acquisition rate of natural diamonds was 9% in 2025, on par with 2021, and up from 8% in 2023. Among more affluent households — those earning $150,000 or more — 15% purchased mined stones in 2025, versus 12% in 2023, De Beers reported.

When it came to gifting, natural diamonds were the most popular choice out of all luxury jewelry items, with 11% of women surveyed selecting that option, compared to 8% who leaned toward jewelry containing synthetics. Some 5% ranked jewelry bearing other precious stones as their first choice, and 4% preferred gold jewelry. Natural-diamond jewelry was also the third-most-popular pick overall to give as a gift, as well as for self-purchasing, behind only a holiday abroad and a weekend getaway. Other non-jewelry choices included a PC or laptop, a spa day, a smartphone, and an experience day, a beauty treatment or a designer handbag.

Millennials were the top purchasing segment for natural diamonds, accounting for 32% of consumers and 55% of demand value. Gen Z represented 18% of consumers and 23% of demand value, while Gen X and Baby Boomers together accounted for 23% of value.

De Beers also sees a ceiling for synthetics when it comes to size. Although falling retail prices for lab-grown mean consumers can afford to purchase larger stones, data from 950 US independent jewelry retailers showed a “noticeable” reduction in pieces sold over 3 carats. That means that if synthetic prices continue to decline, retailers will be unable to upsell to larger sizes, resulting in lower overall sales and impacting gross profits, De Beers added.

For the report, the miner surveyed 18,500 women in the US, aged 18 to 74.