Dr. Copper

"Dr. Copper" is a nickname for copper, which is a metal that is often used as an indicator of the overall health of the global economy. The nickname comes from the fact that copper is widely used in many different industries, including construction, transportation, and manufacturing, so changes in copper prices can provide insight into the strength of these sectors. The idea behind the nickname is that copper, like a doctor, can diagnose the health of the economy. If copper prices are rising, it is typically seen as a sign that the economy is growing and demand for copper is increasing. Conversely, if copper prices are falling, it may indicate weaker economic activity and a decrease in demand for copper.

Commodity trader Dennis Gartman liked to say that copper only had a masters degree in economics and that it is base metals as a whole that have a PhD.