These sparkling stones(?) were found in a southern Vermont trout stream. What are they?
Answer
If only these emerald rocks were jade. Instead, they’re glass slag, the byproduct of an 1800s iron foundry. The pig iron produced at this site was used to make horseshoes for union troops during the civil war, and train tracks that connected Vermont with the Appalachian coal belt. Later, real coal replaced charcoal as an industrial heat source, and much of the nation’s iron work consolidated into the Midwestern and Appalachian coal states. If you’re a history buff, stay tuned for a fascinating article on the wood chemical industry in our Winter issue.