Loose-diamond guide examples start from R3,000; 1ct from R4,000; 2ct from R7,000. Settings are extra. Current prices depend on the IGI certificate and availability. See guide prices.
What buyers want to know first
Diagem supplies IGI-certified lab-grown diamonds and GIA-certified natural diamonds. What the IGI report shows.
Johannesburg, by appointment. Cape Town and elsewhere by arrangement with David. How viewing works.
Engagement rings with a 1-carat lab-grown diamond in 9-carat gold, from R10,000. Choose the diamond first, then plan the setting with David. Lab-grown engagement rings.
Prices are indicative and subject to exchange-rate changes. Confirm your final quote with David.
Choose a loose IGI-certified lab-grown diamond to buy.
Diagem sells loose lab-grown diamonds by enquiry, not blind online checkout. Pick a starting point below — the WhatsApp message is prefilled so David can send current options that match.
By shape
Carat examples
Under 1ct · 1ct · 1.5ct · 2ct · 2ct and larger
Budget examples
Under R5,000 · R5,000 – R10,000 · R10,000 – R20,000 · Over R20,000
Not sure yet? Send rough details. David narrows the choice and explains the differences that actually matter.
Start with a guide price. Confirm with David.
Lab-grown diamond prices change with the IGI certificate, carat, cut, colour, clarity, shape and availability. Use these guide examples as a starting point, then ask David for today’s IGI-certified options.
Loose diamonds only; ring settings are extra. Guide prices only. Diamond prices and availability change. Ask David for current options and up-to-date prices.
Prices are indicative and subject to exchange-rate changes. Confirm your final quote with David.
What changes the price
Carat, cut quality, colour, clarity, shape and the IGI report itself. Two diamonds with the same carat can look and cost very differently.
More diamond for your budget
Lab-grown diamonds usually cost considerably less than natural diamonds of a similar grade, so many buyers choose a larger or better-graded stone for the same budget.
Send your budget, get real options
David quotes IGI-certified diamonds that are available now, not a generic price list.
Choose the diamond first. Build the ring around it.
David helps you balance the loose diamond and setting within your total budget, then guides the design and manufacture.
Engagement rings with a 1-carat lab-grown diamond in 9-carat gold, from R10,000.
Prices are indicative and subject to exchange-rate changes. Confirm your final quote with David.
Gold is a significant part of your ring’s cost. The gold weight, diamond and design all affect the final price.
- Choose the diamond. Send David your preferred shape, carat and total budget. He compares suitable loose IGI-certified options and explains the reports.
- Plan her ring. Share inspiration photos and choose a solitaire, halo, three-stone or bespoke design around your diamond. Review a 3D CAD render before you commit.
- Approve the design and finger size. Specialist trade jewellers make the approved ring to a high standard, with factory-direct pricing.
The same diamond-first approach can be used for bespoke pendants, earrings and other jewellery.




View loose diamonds with David.
Compare suitable loose IGI-certified diamonds side by side at our Johannesburg office, by appointment. Ask David what is physically available to view. Cape Town and other locations are by arrangement with David.

Compare the IGI report before you decide.
Every lab-grown diamond Diagem offers comes with an IGI report. It records the carat, cut, colour, clarity and measurements, so you can compare like with like and know you are buying a real lab-grown diamond — not moissanite or cubic zirconia.
IGI reports at Diagem
At Diagem, lab-grown diamonds use IGI certification. GIA certification applies to Diagem’s natural diamonds.
Read beyond the grade
Cut, polish, symmetry and proportions change how bright and how large a diamond looks. David explains what the report means for the diamond in front of you.
Check before you buy anywhere
Send David a certificate or quote from any seller and he will give you an honest opinion on the grade, the look and the price.

Both are real diamonds. They are not the same.
| Topic | Lab-grown | Natural |
|---|---|---|
| Origin | Grown in a laboratory over a few weeks. | Formed in the earth and mined. |
| Certificate at Diagem | IGI | GIA |
| Hardness and look | Diamond. | Diamond. |
| Price and value | Usually more size or grade for the same budget. | Different rarity, supply and resale factors. |
| Buying help | David can show both side by side and explain the trade-offs honestly. | |
Are lab-grown diamonds real diamonds?
Yes. Lab-grown diamonds are real diamonds created in a laboratory using technology that replicates the conditions under which natural diamonds form deep within the Earth. Instead of taking billions of years, the process takes only a few weeks.
The result has the same crystal structure, brilliance and essential chemical and optical properties as a natural diamond. The key difference is its origin: one grows underground, while the other grows in a controlled laboratory.
Moissanite and cubic zirconia are different materials. If you want a diamond, ask for the IGI lab-grown diamond report.
Already have a lab-grown diamond quote?
Send David the IGI certificate or quote. He will explain the grades, compare the value and tell you whether the option suits your budget — even if you do not buy from Diagem. This is a personal opinion, not a guarantee of price or availability.
What our clients say.
“Absolutely amazing experience dealing with David and his team. Short notice and he pulled it off. No hassle and no BS”
konrad myburgh · 5/5 on Google · 21 September 2026“Absolutely exceptional service. From first contact till delivery David went above and beyond to assist in creating something beautiful. Really recommend!”
Aiden Enslin · 5/5 on Google · 15 September 2026“David's assistance and immediate knowledgeable responses are something to behold.”
Diets Nieuwoudt · 5/5 on Google · 14 September 2026Lab-grown diamond questions
Are lab-grown diamonds real diamonds?
Yes. Lab-grown diamonds are real diamonds created in a laboratory. They have the same crystal structure, brilliance and essential chemical and optical properties as natural diamonds. The difference is origin. They are not cubic zirconia or moissanite.
IGI or GIA: which certificate applies to a lab-grown diamond?
Diagem’s lab-grown diamonds are IGI-certified. GIA certification applies to Diagem’s natural diamonds. If you want a lab-grown diamond, ask for the IGI report.
What does a 1 carat or 2 carat lab-grown diamond cost in South Africa?
As a guide, 1ct lab-grown diamonds start from about R4,000 and 2ct from about R7,000 through Diagem. Guide prices only. Diamond prices and availability change. Ask David for current options and up-to-date prices. Prices are indicative and subject to exchange-rate changes. Confirm your final quote with David.
Can I buy a lab-grown diamond online from Diagem?
No. Diagem does not sell through an online checkout. Send David your shape, carat and budget, compare the IGI-certified options he sends, and decide when you are ready.
Can I view lab-grown diamonds in Johannesburg?
Yes, by appointment. Ask David what IGI-certified lab-grown diamonds are physically available to view and compare in Johannesburg.
Do you see clients in Cape Town or elsewhere in South Africa?
Johannesburg viewings are by appointment. Cape Town and other cities are by arrangement with David. Ask him what can be arranged for your enquiry.
Can I use a lab-grown diamond in an engagement ring?
Yes. Choose the IGI-certified diamond first, then discuss the ring style or a bespoke design made around that diamond and your budget.
Are IGI lab-grown diamonds worth it?
An IGI report tells you the carat, cut, colour, clarity and measurements you are paying for. David compares the report, the look of the diamond and the price so you can judge the value for your budget. Ask him before you buy anywhere.
Do lab-grown diamonds test as diamonds?
Lab-grown diamonds normally test as diamonds because they are diamonds. Specialised laboratory screening can identify laboratory origin, which is why the IGI report matters.
Do lab-grown diamonds become cloudy?
A properly graded lab-grown diamond should not become cloudy simply because it is lab-grown. Clarity, cut quality and care determine how it looks over time.
Already have a quote from somewhere else?
Send David the IGI certificate or quote on WhatsApp. He will explain the grades and tell you honestly whether the option suits your budget. This is a personal opinion, not a guarantee of price or availability.
Find your lab-grown diamond.
Send David your preferred shape, approximate carat, budget and whether you need a ring setting. He’ll help you compare IGI-certified options and arrange the next step when you’re ready.
