Hecla and Coeur Mining stocks jump 13% after Treasury boosts long-term bond buybacks, lowering yields.

Hecla Mining and Coeur Mining shares surged about 13% following the U.S. Treasury's announcement to double buybacks of long-term government debt, which pushed down 10- and 30-year Treasury yields. Lower yields reduce the opportunity cost of holding precious metals, boosting gold and silver prices and benefiting miners with high operating leverage. Despite today's rally, these mining stocks remain flat or modest for the year, indicating the move is a short-term catch-up tied to yield changes rather than a sustained uptrend. Investors should watch Treasury yields closely, as a reversal could quickly reverse gains in mining stocks.