PTRC's survey of nearly 5,000 agate workers found that three-quarters do not own the machines they use. Fewer than one percent buy their raw stones or sell the finished agate. And many take advance ...

Mineral deposits can create markings that look like forests or mountains, and experts say each stone is distinctive. By Jill Newman When Tarun Adlakha displays a dendritic agate, with its finely ...