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许多新鲜的硅质火山岩的金初始含量比以前所认识的明显偏低。所分析的１２９件仔细挑选的玻璃状硅质火山岩样品中，１１３件金含量小于１．０×１０￣（－９），大多只含有≤０．１～０．３）×１０￣（－９）的金。非过碱性流纹岩含金量小于（０．１～０．７）×１０￣（－９），平均金含量为０．２２×１０￣（－９）。强演化、高硅质次碱性和过铝质流纹岩的含金量最低。过碱性流纹岩的平均金含量约为１×１０￣（－９），这表明低ｆ（Ｏ＿２）的聚合熔融体不容易寄存金。２３个相对富硅质中性岩石样品的平均金含量为０．５４×１０￣（－９），拉斑玄武安山岩（铁安山岩）中的金一般高于钙碱性类型。几乎没有任何证据表明特殊地质区域的金真正高于其它区域。总成分、熔体结构、蒸气分离时间和数量、矿物、硫化物和／或金属熔融体相可以表现出主要决定硅质岩浆的金含量。根据分离蒸气、结晶及不混熔熔融体相由岩浆排出金的多方面资料表明，新鲜火山岩只有极低的岩浆金浓度。在多数情况下，岩浆值会更高。某些斑岩矿床的上升金含量（０．３×１０￣（－６）～＞１．０×１０￣（－６））表明硅铝质岩浆的金浓度明显高于玄武岩（１～２）×１０￣（－９）的金浓度。
The initial gold content of many fresh siliceous volcanic rocks is significantly lower than previously recognized. Of the 129 carefully selected vitreous siliceous volcanic rocks analyzed, 113 had less than 1.0 × 10 -9 gold, most of which contained only ≤0.1 to 0.3 × 10 -9 ) Of gold. Non-overbased rhyolite gold content of less than (0.1 ~ 0.7) × 10 ~ (-9), the average gold content of 0.22 × 10 ~ (-9). Strong evolution, high siliceous alkaline and rhyolite rhyolite gold content is the lowest. The average gold content of overbased rhyolite is about 1 × 10 ~ (-9), which indicates that the polymerized melt with low f (O_2) is not easy to deposit gold. The average gold content of 23 relatively siliceous, neutral rock samples is 0.54 × 10 ~ (-9). The gold content in the basalt Andesite (iron andesite) is generally higher than that of the calcareous alkaline type. There is very little evidence that gold in special geological areas is really higher than in other areas. The total composition, the melt structure, the time and amount of vapor separation, the mineral, the sulfide and / or the molten phase of the metal may show a major contribution to the gold content of the siliceous magma. Various sources of gold from magma to separate vapors, crystals, and unmelted melt phases suggest that fresh volcanic rocks have only very low magma concentrations. In most cases, the magma will be higher. The ascending gold content of some porphyry deposits (0.3 × 10 -6 ~ 1.0 × 10 -6) indicates that the gold concentration of sialon magma is significantly higher than that of basalts (1-2) × 10 ~ (-9) gold concentration.