Regional volcanic strata are the source of placer gold and laterization process is the main stage of formation of placer gold.
区域火山岩地层砂金的矿源,地表赤红壤化砂金形成的主要段。
Regional volcanic strata are the source of placer gold and laterization process is the main stage of formation of placer gold.
区域火山岩地层砂金的矿源,地表赤红壤化砂金形成的主要段。
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