Silver September futures opened at $65.90 per ounce on Tuesday, August 18, 2026, down 0.5% from Monday's closing price, then fell to $65.12 by 9:11 a.m. ET. The price fluctuated between $65 and $66 an ounce Tuesday morning as negotiations with Iran appeared to have stalled. A 60-day agreement between the U.S. and Iran to pursue a diplomatic resolution expired Monday with no alternative deal in place, leading to higher oil prices and U.S. Treasury yields.