Lesson1 Part1

Metallic Ores An ore can be described briefly as an accumulation of mineral in sufficient quantity as to be capable of economic extraction. 一个矿石可以简单地描述为一个足够数量的、能够经济开采的矿藏。 This establishes the market price of the metal as a critical criterion in the definition, and this will vary according to the com……Read More