We assume you are converting between milligram and gram. You can view more details on each measurement unit: milligrams or gram. The SI base unit for mass is the kilogram. 1 kilogram is equal to 1000000 milligrams, or 1000 gram.
Copper, in spiritual alchemy, represents experiences with love, sympathy and affection. The world would be a harsh, bleak land without the refining influence of copper. There would be no appreciation of beauty, no knowledge of harmony; none of the softer shading of life that soothe the sting of adversity.
I believe since it was an alloy, and not something pure like silver, gold or copper, I believe there is a spiritual significance to that too. Revelation 1:15 And his feet like unto fine brass, as if they burned in a furnace; and his voice as the sound of many waters.