Lab-Grown Diamonds: From Bridal Boom to Deep-Tech Battlefield

• US drives ~70% of global lab-grown jewellery demand.

• China produces ~22 million carats of gem-quality stones annually.

• India polishes over 90% of global rough supply.

• Wholesale prices fell up to 90% due to overcapacity.

• Future growth lies in semiconductor and quantum-grade diamond wafers.

The narrative around lab-grown diamonds (LGDs) is often simplified into a retail storyline — rapid adoption, falling prices, and margin pressure. But that framing overlooks a much broader structural shift. Over the past decade, the United States, India, and China have collectively shaped a multi-layered lab-grown diamond economy spanning industrial abrasives, consumer jewellery, and advanced technology applications.

Each layer operates with its own production hubs, trade routes, and demand cycles. Leadership in one segment does not guarantee dominance in another.

A Three-Country Closed Loop

The consumer jewellery segment is effectively a tightly interlocked triangle connecting the US, China, and India — a system so concentrated that removing any one participant would destabilise the entire chain.

On the demand side, the United States stands unrivalled. It accounts for roughly 70% of global lab-grown jewellery sales. Lab-grown stones now appear in nearly six out of ten American engagement rings, making US bridal culture the category’s central revenue driver. Without American buyers, other markets lack the scale to absorb current production volumes.

On the supply front, China leads decisively. Industry estimates suggest the country produced around 22 million carats of gem-quality lab-grown diamonds in 2024, roughly three-fifths of global output. Trade figures also indicate China exported about 35 million carats of rough lab-grown stones in 2025. Massive capacity expansion in China has been instrumental in driving prices down to levels that made lab-grown diamonds mainstream.

India occupies the crucial midstream position. Surat-based processors polish more than 90% of the world’s rough lab-grown diamonds. Following significant capital investment, India’s reactor fleet is estimated at 8,000 to 10,000 machines — roughly double its capacity from just a few years ago. In financial year 2025–26, India exported 18.8 million carats of polished lab-grown diamonds, surpassing its polished natural diamond exports of 16 million carats by volume for the first time. Cutting costs in Surat remain remarkably competitive at around $60 per carat, a benchmark difficult for any other polishing centre to match profitably.

Boom, Bust, and Survival

This interconnected trio not only built the jewellery boom but also triggered its wholesale price collapse. Rapid capacity additions in China and India flooded the market, pushing wholesale prices down by as much as 90%.

The segment has endured largely because US retailers maintained strong margins, cushioning falling wholesale costs with relatively stable retail pricing. In effect, China absorbs pressure at the growing stage, India at the polishing stage, while American retailers capture the margin spread that sustains storefront profitability.

The system is mutually dependent. Remove any link — US demand, Chinese production, or Indian processing — and the global jewellery loop would struggle to function.

Beyond Jewellery: Diverging Paths

While the jewellery narrative dominates headlines, the more consequential shift may be unfolding in industrial and deep-technology applications.

At the lower end, China’s Henan province continues to anchor global production of industrial-grade diamond grit. Using extensive cubic press fleets, manufacturers produce billions of carats for construction and mining, where prices are measured in cents per carat.

At the high end, however, a distinct ecosystem is emerging. Advanced, wafer-scale single-crystal chemical vapour deposition (CVD) diamonds — essential for semiconductors, high-power electronics, optics, and quantum computing — are largely produced by specialised firms in the United States, Japan, and Europe. This tier is technologically separate from both jewellery and industrial grit production.

The barrier to entry is steep. While generic CVD reactors can produce stones suitable for budget jewellery, manufacturing semiconductor-grade diamond wafers demands exceptional control over purity, nitrogen-vacancy concentrations, isotopic consistency, and atomic-level surface finishing. These capabilities require capital, intellectual property, and highly specialised expertise.

The Strategic Fork Ahead

The industry now stands at a crossroads. Countries and companies that continue focusing solely on carat volume in the commoditised jewellery tier may face shrinking margins and intense competition. Meanwhile, the emerging deep-tech segment rewards early investment and technical sophistication.

Waiting for the high-tech market to mature carries risks. By the time large-scale demand materialises, patents, supply agreements, and established partnerships may already dominate the landscape.

In the coming decade, leadership in lab-grown diamonds may hinge less on counting output volumes and more on mastering crystal perfection. The competitive edge will belong to those who shift from scaling production to refining precision — moving from carats to quantum.