Learn About Lab Grown Diamonds

Lab-grown diamonds, also known as created or man-made diamonds, are produced in controlled laboratory environments rather than forming naturally in the Earth’s crust over millions of years. These diamonds have the same chemical, physical, and optical properties as natural diamonds, as they are made of carbon atoms arranged in a crystal lattice structure. Today, lab-grown diamonds account for over 15-20% of global diamond jewellery sales, and typically cost 30-50% less than comparable natural diamonds. Due to their faster production cycle, often completed within a few weeks, lab-grown diamonds have gained popularity among price-conscious consumers.

Why lab grown diamonds?

  • Lab-grown diamonds can generate up to 60-70% less carbon emissions than mined diamonds, as they avoid large-scale mining, land disruption, and heavy fuel use.
  • Lab-grown diamonds are often more budget-friendly than natural diamonds of similar quality, making them an attractive choice for those looking for value.
  • Lab-grown diamonds typically cost 30-50% less than natural diamonds of similar cut, colour, and clarity, offering better value for money.

How are lab grown diamonds made?

  • The process begins with a small diamond seed or a thin slice of an existing diamond crystal. This serves as the starting point for the crystal growth.
  • A diamond seed is placed with a carbon source and metal catalyst under high heat and pressure, replicating Earth’s mantle conditions.
  • Under these conditions, carbon atoms dissolve in the molten metal and precipitate onto the diamond seed, layer by layer, gradually growing the diamond crystal.
  • The cell is slowly cooled over several weeks to allow the newly formed diamond to solidify and grow to the desired size.

Diamond seed preparation

  • Starts with a thin slice of diamond seed (typically 0.5-1mm) that acts as the base for crystal growth in the lab.
  • The seed is carefully polished and precisely positioned with accuracy above 95% to guide the diamond’s crystal structure.
  • This seed determines the orientation, clarity, and overall quality of the final grown diamond, influencing up to 80% of its crystal structure.
  • Carbon atoms attach to the seed over time, allowing the diamond to grow layer by layer under controlled conditions.

Carbon deposition and diamond growth

  • Carbon is exposed to the extreme heat and pressure inside the growth chamber, at temperatures of 1300-1600 degree celsius and pressures of 5-6 Gpa, similar to conditions those deep within the Earth’s mantle.
  • The carbon source melts and dissolves into the molten metal catalyst.
  • Carbon atoms move toward the diamond seed under controlled conditions.
  • These atoms bond to the seed, forming diamond layers and growing the crystal, at an average growth rate of 0.1-0.3mm per day.

Diamond purification

  • The grown diamond is removed from the high pressure cell after a growth cycle of approximately 2-6 weeks.
  • Excess carbon and metal catalyst are carefully separated from the diamond with removal efficiency of over 95%.
  • Chemical and thermal treatments clean the diamond surface at temperatures ranging from 600-1000 degree celsius to remove impurities.
  • The result is a pure diamond crystal ready for cutting and polishing with purity levels exceeding 99.9% carbon.

POLISHING OF A LAB-GROWN DIAMOND

  • The rough lab-grown diamond is carefully examined to plan the best cut, using 3D mapping and analysis that can improve cut yield by 10-20%.
  • Laser or mechanical cutting is used to shape the stone precisely, with cutting accuracy within 0.01 mm.
  • Facets are polished to enhance brilliance, fire, and symmetry, often achieving Excellent or Very Good cut grades in over 90% of finished diamonds.
  • The finished diamond is inspected for quality and ready for setting.

Transparency and traceability

  • The process begins by placing a thin “diamond seed” into a vacuum chamber, typically 0.5-1mm thick and precisely align for uniform growth.
  • A mixture of methane and hydrogen gases is introduced and ionized using microwave energy or plasma to break them down into carbon atoms.
  • These carbon atoms are deposited onto the seed, adhering to its surface and building the diamond layer by layer.
  • Once the desired size is reached, the diamond is cooled and then undergoes professional cutting and polishing to achieve its final shape.

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