On this page
Natural diamonds formed deep inside the earth over one to three billion years. Laboratory-grown diamonds are grown above ground in weeks, using the same element, carbon, in the same crystal structure. This guide explains how each is made, what is the same and what is different, so you can decide which you prefer. Zarna Jewels works only with laboratory-grown diamonds; we do not sell natural diamonds.
How natural diamonds form
- Carbon deep in the earth’s mantle, around 150 km down, is exposed to immense heat and pressure.
- Over roughly one to three billion years, it crystallises into diamond.
- Deep volcanic eruptions carry diamonds towards the surface in rock called kimberlite.
- The diamonds are mined, sorted, then cut and polished. Only some rough diamonds are good enough for jewellery.
Diamonds have been treasured for more than 2,000 years; the earliest were found in riverbeds in India.
How laboratory-grown diamonds are made
A laboratory-grown diamond starts from a thin slice of diamond, called a seed. In the CVD (chemical vapour deposition) process, the seed sits in a chamber filled with carbon-rich gas, which is heated into a plasma; carbon atoms settle on the seed layer by layer and grow into a rough diamond over several weeks. The other method, HPHT (high pressure, high temperature), recreates the conditions deep in the earth in a press. The rough diamond is then cut and polished exactly like a natural one. Read more in our laboratory-grown diamonds guide.
Natural and laboratory-grown diamonds compared
| Natural diamond | Laboratory-grown diamond | |
|---|---|---|
| Made of | Carbon in a diamond crystal | Carbon in the same diamond crystal |
| Hardness | 10 on the Mohs scale | 10 on the Mohs scale |
| Brilliance and fire | Depends on the cut | Depends on the cut, in exactly the same way |
| How it forms | In the earth, over one to three billion years | In a laboratory, in weeks |
| Grading | 4Cs; the report states natural origin | The same 4Cs; the report states laboratory-grown origin |
| Price for the same size and grade | Higher | Much lower |
| Supply | Limited by mining | Grown to order in many sizes and shapes |
Can you tell them apart?
Not by eye, and not with the handheld testers many jewellers use, because both are diamond. Gem laboratories identify the origin with specialist equipment that reads tiny differences in growth patterns and trace elements. That is why a grading report from a laboratory such as IGI states the origin, and why laboratory-grown diamonds must always be described as laboratory-grown when they are sold.
Which should you choose?
- Choose a natural diamond if its geological age and rarity are what matter most to you.
- Choose a laboratory-grown diamond if you want the look and durability of a diamond with a larger stone or higher grade for your budget, and a supply chain you can follow from the rough to the setting.
At Zarna Jewels, our parent company Sheladiya Diamond has worked in diamonds since 1983. Today we buy CVD rough from trusted growers, then cut, polish and set the diamonds ourselves in Surat. Explore our engagement rings.
Frequently asked questions
Are laboratory-grown diamonds the same as natural diamonds?
They have the same chemical composition, crystal structure, hardness and optical properties. The difference is their origin, which a gem laboratory can identify and which the grading report states.
Do laboratory-grown diamonds last as long?
Yes. A diamond is a diamond in hardness and durability: both score 10 on the Mohs scale and are suited to everyday wear.
Why are laboratory-grown diamonds less expensive?
They are grown in weeks rather than mined, so they cost much less to produce and supply is not limited by mining.
Does Zarna Jewels sell natural diamonds?
No. We work only with laboratory-grown diamonds.
