We were excited to see bits of agate in some of the stones, and we filled our buckets to the brim. Formed mostly in the ...

The Smithsonian’s National Museum of Natural History has acquired the 2.33-carat "Winston Red Diamond," as part of the “Winston Fancy Color Diamond Collection.” ...

They can look similar to bubbles in soap or oil over water that give a rainbow appearance. They also have a similar appearance to the rainbow observed on a mother-of-pearl gemstone. Sign up for our ...