Silver can be invested in through physical bullion, coins, exchange-traded products, futures, and mining shares, driven by both industrial uses (electronics, photovoltaics) and investment demand. The U.S. Geological Survey estimated 2025 world mine production at 26,000 metric tons and reserves at 610,000 metric tons, noting that it is primarily recovered as a byproduct of lead-zinc, copper, and gold mines. The Silver Institute reported total demand fell 2% in 2025 to 1.13 billion troy ounces—industrial demand declined 3% while coin and net bar investment rose 14%—resulting in a fifth consecutive year of supply deficits. Silver prices, quoted in U.S. dollars per ounce, are highly correlated with gold (a 1981 study found a 0.83 correlation), though the gold-silver ratio varies—historically fixed at 15:1 by the Coinage Act of 1792. Recent price rallies are fueled by investment demand, supply deficits, safe-haven flows, and industrial prospects in AI data centers, solar cells, and electric vehicles. Because silver has a smaller and more volatile market than gold, its value is heavily influenced by both macroeconomic and industrial factors.