Treated diamonds are surprisingly more common than you might think. While treated gems were often looked down upon in the beginning, it has become more acceptable over the years because of their ability to make purchasing a diamond engagement ring more economical for couples.
What are Treated Diamonds?
A treated diamond is one that has undergone a process to enhance the appearance of the stone. Treatments can be used to alter or enhance the color of a diamond or minimize the appearance of flaws, thereby enhancing the overall look.
Synthetic or imitation diamonds (stones that have been created in a lab) are made to look very close to the real thing. For most people, a synthetic diamond can substitute for a natural diamond with no one the wiser unless they have a trained eye.
Natural diamonds that have been treated usually undergo a treatment process to enhance the overall appearance of the stone, thereby (hopefully) increasing its value.
What Types of Treatments are There?
To enhance the quality of a diamond, there are several types of treatments that can be used. Certain processes are more popular than others, and specific treatments can be used to create “fancy” colored diamonds.
- High Pressure/High Temperature (HPHT)
This process means exactly what it says – a treatment of high pressure combined with high temperature can be used to create a variety of colors. It can make a diamond less colorful or create pink, yellow, brown or blue diamonds.
- Irradiation
It sounds scary, but using radiation to alter the color of a diamond is actually quite common. Irradiation treatments can create black, green or blue diamonds.
- Heat
A different and less potentially dangerous method of creating black diamonds, heat treatment can produce black diamonds by exposing a lower-quality diamond to intense temperatures over a period of time.
- Irradiation and Heat Treatment
When used together, diamonds can be altered to a variety of colors. First, a diamond is exposed to radiation followed by a period of intense heat treatment to form purple, blue, yellow, pink and brown diamonds.
Other treatment methods involve correcting inclusions and other flaws in a diamond to enhance the overall appearance of the stone.
Other Things to Consider
All jewelers are required to disclose whether the diamond you purchase has been treated or not. If you are knowingly purchasing a treated diamond, make sure you ask the jeweler for information regarding the treatment; i.e., when it was done, what special care instructions there are, if any, and what type of guarantee the company offers if a treated stone ever needs repairs.
Purchasing a treated diamond can be a lot more economical for couples who are on a tight budget. Don’t let the fact that the stones have been treated scare you away – treated diamonds can still be used to make beautiful engagement rings.

