Why Online Diamond “Bargains” Are Rare
Today, internet-savvy buyers have some understanding of how diamonds are valued and may even have access to wholesale references such as the Rapaport Diamond Report. Elaborate guarantees, impressive certificates, and so-called “bargain prices” offered by obscure websites can therefore appear convincing.
What many buyers do not understand is how price lists are actually used, or what determines a fair and realistic market price. Well-proportioned, certified diamonds trade internationally at prices known to professional dealers. When a diamond is offered substantially below this level, there is usually a specific and undisclosed reason.
When the Bargain Isn’t a Bargain
From time to time, an internet buyer will visit our office seeking reassurance about a diamond purchased online, or requesting that it be set into jewellery. The disappointment is often considerable when it becomes clear that the apparent bargain was no bargain at all.
In most cases, the low price can be explained by one or more of the following factors.
Common Online Diamond Scams and Pitfalls
- Stolen diamonds. Illicitly sourced diamonds have no legitimate cost base, must be moved quickly, and are sold cheaply. Purchasing such diamonds carries significant legal and ethical risk.
- Over-graded diamonds. Diamonds graded by laboratories known for generous grading practices may be worth 30–40% less than equivalent diamonds certified by strict laboratories such as GIA.
- Discounted characteristics. Diamonds with old cutting styles, poor proportions, or very strong fluorescence may be discounted by up to 40% due to reduced visual appeal or market demand.
- False or unreliable grading reports. Some grading reports are issued by individuals without recognised qualifications or traceable laboratory addresses.
- Mismatched certificates. The diamond offered does not correspond to the grading report provided. Only a qualified diamond expert can confirm whether a diamond matches its certificate.
- Undisclosed treatments. High Pressure–High Temperature (HPHT) processes may be used to improve the colour of brown diamonds. Not all laboratories can detect such treatments, and certificates from those laboratories may be unacceptable in the professional market.
- Laboratory-grown diamonds sold as natural. Synthetic diamonds have been sold online as natural diamonds. Many jewellers lack the advanced equipment required to distinguish reliably between the two.
- Clarity enhancement. Laser drilling or fracture filling may be used to improve apparent clarity. These treatments are sometimes not disclosed, and many online buyers are unaware of their implications.
Caveat Emptor
Buyers should use the internet as a learning tool, but nothing replaces the expertise, accountability, and service of an established brick-and-mortar jeweller. Purchasing a diamond is a significant and meaningful occasion, and informed guidance ensures that it remains a positive and lasting experience.
By Dr Petre Prins
Managing Director, Prins & Prins Diamonds
PhD, MBA | Geology, Mineralogy & Geochemistry
Cape Town, South Africa