Lab-Grown vs Natural Diamonds in New Zealand: What You Need to Know

What Are Lab-Grown Diamonds?

Lab-grown diamonds are real diamonds created in controlled laboratory environments rather than formed deep within the Earth over billions of years. They share the exact same chemical composition (pure carbon, crystallised in a cubic structure), physical properties, and optical characteristics as natural diamonds. In simple terms, a lab-grown diamond is a diamond. It is not a simulant like cubic zirconia or moissanite.

There are two main methods used to create lab-grown diamonds:

• HPHT (High Pressure High Temperature): This method replicates the conditions found deep underground. A small diamond seed is placed in a press and subjected to extreme heat (around 1,500°C) and pressure, causing carbon to crystallise around the seed.
• CVD (Chemical Vapour Deposition): A diamond seed is placed in a sealed chamber filled with a carbon-rich gas, typically methane. The gas is heated until carbon atoms separate and deposit onto the seed layer by layer, growing the diamond over several weeks.

Both methods produce gem-quality diamonds that are certified by the same internationally recognised grading laboratories, including the GIA (Gemological Institute of America) and IGI (International Gemological Institute). These certificates evaluate the same 4Cs you would expect for any natural diamond: cut, colour, clarity, and carat weight.

How Do They Compare?

Here is a side-by-side comparison of the key differences and similarities between lab-grown and natural diamonds:

Price Differences in New Zealand

One of the biggest reasons New Zealand buyers consider lab-grown diamonds is the price. For a 1-carat round brilliant diamond of good quality (say, G colour, VS2 clarity, excellent cut), you can expect the following approximate NZD price ranges:

• Natural diamond: NZ$8,000 to NZ$15,000, depending on the specific colour, clarity, and cut quality.
• Lab-grown diamond: NZ$2,000 to NZ$4,000 for a comparable stone.

It is worth noting that diamond prices in New Zealand tend to be higher than in the United States or other large markets. This is partly due to import costs, GST, and the smaller size of the NZ market. However, both natural and lab-grown diamonds are widely available here, and a reputable New Zealand jeweller can source either type for you.

Lab-grown diamond prices have dropped significantly over the past few years. Globally, wholesale prices for lab-grown stones have fallen by roughly 75–80% since 2020, as manufacturing capacity has increased. This means that for the same budget, you can now get a noticeably larger or higher-quality lab-grown diamond than would have been possible just a few years ago.

For many couples in Auckland, Wellington, and Christchurch, this price difference is the deciding factor. A lab-grown diamond lets you put more of your budget towards the setting and design of the ring itself, whether that is a classic solitaire, an eye-catching halo design, or a meaningful trilogy ring.

Quality and Appearance

This is the point that surprises many people: lab-grown and natural diamonds are identical to the naked eye. They have the same sparkle, the same fire, and the same brilliance. Even experienced jewellers cannot distinguish between them without specialised testing equipment.

Both types of diamond are graded using the same 4Cs system. A lab-grown diamond with an excellent cut, G colour, and VS1 clarity will look and perform exactly the same as a natural diamond with those grades. They have the same refractive index (2.42), the same hardness (10 on the Mohs scale), and the same thermal conductivity.

Lab-grown diamonds can contain inclusions, just as natural diamonds do. They go through the same rigorous grading process, and lower-quality lab-grown diamonds are graded accordingly. So it is important to check the certificate and choose a well-cut stone regardless of which type you select.

In practical terms, no one looking at your engagement ring will be able to tell whether the diamond is lab-grown or natural. The difference is in the story of how it was made, not in how it looks on your finger.

Environmental and Ethical Considerations

Environmental and ethical factors are increasingly important to New Zealand buyers, and both lab-grown and natural diamonds have their own considerations here.

Lab-Grown Diamonds

Lab-grown diamonds do not require any mining, which means no land disturbance, no habitat disruption, and no community displacement. This is a significant advantage for buyers who are concerned about the ecological impact of mining.

However, producing lab-grown diamonds is energy-intensive. Growing a single diamond can require substantial electricity, and the carbon footprint depends heavily on the energy source used by the laboratory. Some manufacturers now use renewable energy, but this is not universal.

Natural Diamonds

Modern natural diamond mining has come a long way from its troubled past. The Kimberley Process, established in 2003, works to prevent conflict diamonds from entering the supply chain. Many mining companies now invest in local communities, environmental rehabilitation, and sustainable practices.

Natural diamond mining also provides employment and economic support to communities in countries like Botswana, Canada, and Australia. For some buyers, supporting these communities is an important part of their purchase decision. At Diamond Rings NZ, we source our natural diamonds from ethically responsible suppliers with fully traceable supply chains.

Resale Value and Long-Term Worth

It is important to be upfront about this: natural diamonds hold their value better than lab-grown diamonds. While no diamond is a guaranteed investment (you will typically recover only a fraction of the retail price if you resell), natural diamonds have a more established secondary market and more predictable pricing.

Lab-grown diamond prices have been falling steadily as production technology improves and more manufacturers enter the market. A lab-grown diamond you purchase today may be worth significantly less in five or ten years if current pricing trends continue. This is worth considering if resale value matters to you.

That said, the vast majority of people never resell their engagement ring. It is a piece of jewellery with deep personal significance, not a financial asset. If you are buying a ring to wear and treasure for a lifetime, the resale question may be less relevant than you think. What matters most is choosing a diamond that you love and that fits your budget. For more guidance on what to look for in a ring, see our guide on how to choose the perfect engagement ring in New Zealand.

Which Should You Choose?

There is no single right answer here. The best choice depends on what matters most to you as a couple. Here are a few things to consider:

• Budget is your top priority: A lab-grown diamond gives you more size and quality for your money. You could put the savings towards a more detailed setting, a wedding band, or the honeymoon.
• You value tradition and rarity: Natural diamonds carry a sense of geological wonder. Knowing your diamond formed billions of years ago can add a unique emotional dimension.
• Environmental concerns are important: Both options have trade-offs, but lab-grown diamonds avoid the direct environmental impact of mining. If this is a priority for you, a lab-grown diamond may feel like the better fit.
• Long-term value matters: If you want the diamond to retain as much value as possible over time, a natural diamond is the safer choice.
• You want the biggest, best-looking stone: Lab-grown diamonds allow you to go larger within the same budget. A 1.5-carat lab-grown diamond may cost less than a 1-carat natural of similar quality.

Both lab-grown and natural diamonds make beautiful engagement rings. Both will last a lifetime. Both will sparkle on your partner’s finger every single day. The choice comes down to your personal values, your budget, and what story you want your ring to tell.

See Both Options at Diamond Rings NZ

At Diamond Rings NZ, a division of Polished Diamonds (established 1969), we carry both lab-grown and natural diamonds across our full range of engagement ring styles. Our experienced team can walk you through the differences in person, show you stones of each type side by side, and help you find the perfect diamond for your ring and your budget.

We have showrooms in three locations across New Zealand:

• Auckland – Ponsonby High Street
• Wellington – Waterfront CBD
• Christchurch – Central Business District

Whether you are leaning towards a lab-grown diamond, a natural diamond, or you simply want to see and compare both before making a decision, we are here to help. Every ring we create is customised to your preferences and crafted with the same care and attention to detail, regardless of which type of diamond you choose.