The seller told her it was a rough brown diamond. Runsdorf, in disbelief, said she wanted it verified by the Gemological Institute of America. Sure enough, it came back as a certified 65-carat ...

making them appear green. Whatever the reason, diamonds come in a rainbow of bright, beautiful colors, and then there are brown diamonds. For centuries, brown diamonds were cheap. They were ...

Brown diamonds are caused by the crystal becoming deformed ... Blue diamonds only need a tiny amount of boron to produce colour, but they are much rarer than yellow ones. A green diamond means it has ...