Technological innovations have replaced mercury in batteries, dental fillings, and thermometers: mercury consumption is down 98% and, by 2000, the price was down 90%. More broadly, since 1946, supplies of copper, aluminum, iron, and zinc have outstripped consumption, owing to the discovery of additional reserves and new technologies to extract them economically.
但是，即使商品价格最近有所反弹，但总体而言已下跌至150年前水平的三分之一。技术创新取代了电池、假牙材料和温度计中的汞，到2000年，汞消费量下降了98%，价格下跌了90%。更广地说，自1946年以来，铜、铝、铁和锌供给都超过了需求，这要归功于新储量的发现和更经济的新提炼技术。