Nativegold is a naturally occurring gold mineral. It is a kind of natural gold bullion produced from vein ore or placer. Because the shape is similar to the head shape of a dog, it is also called dog head gold. It often contains silver or trace copper. Isometric. Generally, it is a loose granular or irregular dendritic aggregate, and individual blocks can weigh dozens of kilograms. The color and stripes are golden yellow. It has metallic luster, hardness of 2.5-3.0, strong ductility, and specific gravity of 15.6-19.3.
Passing by a gravel field or a coal pile, have you ever been attracted by a little golden light? Many people have been teased by these small particles shining with gold, even the famous British explorer captain John Smith.
At the beginning of the 17th century, Captain John Smith sent a whole ship of rocks containing this golden particle to London as a trophy for exploring the chick hamney River in Virginia, but the test results given by the London side were disappointing - it was just a pile of worthless "fool's gold".
Captain John Smith and his map of Virginia.
What is fool's gold? It is a common sulfide mineral on the earth. Its official name is pyrite and its English name is pyrete. Just like its name, the chemical composition of fool's gold is ferrous disulfide, which has nothing to do with gold, but its golden color and shiny metallic luster like gold make ordinary people deceived by it if they are not careful.
In order to prevent being fooled by friends who have also read this article, here is also a way to distinguish pyrite from natural gold: pyrite has a high hardness, and the Mohs hardness can reach 6 - 6½, So ordinary knives can't hurt it at all, while the hardness of natural gold is only 2½- 3. It can be cut with a knife; Pyrite is brittle and will break into powder when hammered, while natural gold has good ductility and will turn into a gold cake after hammering; In addition, the stripes drawn by natural gold on the unglazed white porcelain plate are still gold, while the stripes drawn by pyrite are green and black, which is also one of the important methods to distinguish the two.
Although the value of pyrite is negligible compared with gold, it is not always worthless. Pyrite is an important chemical raw material. Sulfur dioxide widely used in the paper industry and sulfuric acid commonly used in chemical industry are basically produced by pyrite, which is accompanied by trace gold, silver and other precious metals, which can also be comprehensively utilized.