Many diamonds are mined in areas with deplorable working conditions and violence. You can avoid these “conflict diamonds” by looking for a stone with a Kimberley Process Certification Scheme (KPCS) certification. Its members—countries that mine and sell diamonds, gem-industry pros, and human rights organizations—pledge not to trade or sell “rough diamonds used by rebel movements or their allies to finance armed conflicts aimed at undermining legitimate governments.”

Unfortunately, the KPCS certification has been difficult to enforce. Diamond smugglers still channel conflict stones into the market, and the KPCS has done little to prevent the continued sale of stones mined in inhumane and violent conditions.

If this issue is important to you, look for the KPCS designation or other even stricter standards. For example, the online gem store Brilliant Earth offers what it calls a “Beyond Conflict Free Diamond Guarantee” that its products are purchased only from mines it can verify as environmentally friendly and having ethical working conditions. Also look at diamond origins: Most mines in Canada, Namibia, and Botswana have high labor and environmental standards. Or check out lab-grown diamonds.