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如表1所示，地壳中锆的丰度超过铜、锌、锡、镍和铅。铪在地壳中的丰度估计超过了汞、铌和铀，锆和铪被称为稀有金属，主要是因为它们的制备方法比较困难，工艺比较复杂。已发现锆铪矿物40多种，主要集中在花岗岩碱性伟晶岩中，均属氧化物矿物。铪不是一种独立的矿物，常与锆伴生。具有工业价值的锆矿石有锆英砂和斜锆石，斜辉石和斜辉石有时用作工业原料。锆和铪的主要矿石和成分见表2。
表1地壳中锆、铪及某些元素的丰度比较
苏园
质量分数/× 10-3%摩尔分数/× 10-4%苏园质量分数/× 10-3%摩尔分数/× 10-4%表2主要锆铪矿物类型①
矿物名称
化学成分密度/(克厘米-3)
困难颜色ωZrO2/%ωHfO2/%下一篇：沙特对外投资(沙特外交政策)