Abandoned coal mines had left waterways acidic and rusty orange. Local residents are cleaning them up, and recovering valuable minerals in the process. By Mira Rojanasakul Mira Rojanasakul revisited ...

Do you know a child who finds endless wonder in nature and expresses that wonder by collecting EVERYTHING, from shells to sticks to rocks? Exploring and collecting are signs of intellectual curiosity.

Rocks and minerals are closely related, but there are fundamental differences between the two. When you purchase through links on our site, we may earn an affiliate commission. Here’s how it works.