How did the ancients look for minerals in ancient times without metal detectors

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In China's five thousand years of history, smart and hardworking Chinese people have absorbed a lot of resources from nature to reproduce. China developed mineral resources very early. After the Stone Age, China entered the Bronze Age, which opened the history of the development and utilization of China's metal minerals. The use of these metals has not only greatly enhanced the productivity of the Chinese people and improved the lives of countless people, but also left countless exquisite cultural treasures for future generations. Such amazing bronzes as Siyang Fangzun, Si (Hou) Mu Wu Ding, as well as Goujian Jian, the King of Yue who is still sharp thousands of years later, and the iron and steel fire to defend the country, are all the achievements of the Chinese people in the development and utilization of metal minerals.

Simu Wuding, the aggregator of bronze wares

Bronze ritual vessels in ancient times

China's development of metal minerals began in the late Xia Dynasty, when China entered the Bronze Age. The scale of the use of bronze ware reached its peak in the Shang Dynasty, and the bronze handicraft industry developed greatly as a result. In the Spring and Autumn period, China has developed mining technology and smelting and casting technology. In addition to copper mining, lead and zinc, as important metals in bronze alloys, have also been mined and developed. After the warring States period, China moved from the Bronze Age to the Iron Age, when the scale of iron ore mining was getting larger and larger, and the iron cast by pig iron was gradually integrated into the lives of thousands of families. In addition, for some precious metals such as gold, silver and so on, the development and utilization of these metals also began a long time ago. Of course, the development and utilization of so many metals is inseparable from the ancient experience of prospecting and prospecting.

Guan Zhongxiang (Biography of Ancient Sages, Volume 1)

Among the various prospecting theories, the most famous one is Guanzi several articles in the warring States period, in which there is a systematic summary of the exploration of iron, copper, zinc, lead, gold, silver and mercury. It is mentioned in the book that "if there is ochre on the mountain, there is iron under it; if there is lead on it, there is silver under it; if there is red sand on it, there is gold under it; for those who have mercy stone above, there is copper and gold under it." The view of this mountain is also "those who are honorable" and "those with mausoleum above, lead, tin and red copper below". With the increasingly in-depth study of mineral resources in China, Xia Xiangrong and other mineral geologists of the older generation summed up the prospecting experience of Guanzi several articles into six formulas, called "Guanzi Liuyi", namely, "those with ochre above have iron; those with mercy above have copper and gold; those with lead above have silver; those with red sand above have gold; those with mausoleum above have lead, tin and red copper; those with silver above have lead under them". In the long process of prospecting, these six prospecting formulas provide a lot of guidance for mineral exploration in our country.

The site of the Tongluoshan deposit in Chongqing

There's ochre on top and iron on bottom.

Ochre here refers to hematite (Fe2O3). The ancients found that when reddish-brown hematite appeared above a place, large iron ore appeared below. The iron ore here usually refers to skarn iron ore, and the famous Daye iron ore in China is this type of iron ore. During mineralization, hot and iron-rich magma intrudes into carbonate rocks to form iron ore. A large number of magnetite ores can appear in the main metallogenic period, while pyrite and siderite ores are formed in the later stage. Of course, the ochre here, that is, hematite may be associated in the metallogenic period, but it is more likely that all kinds of iron ore formed crimson iron ore due to late weathering. In large iron ore, high-grade iron ore is exposed to the surface and weathered to form hematite, and the ancients looked for the iron ore enriched below based on the ochre exposed.

Metallogenic model map of skarn iron ore (L. D. Meinert,1993)

Hematite

Daye Iron Mine

There is copper and gold under the mercy stone.

Cishi is what we now call magnetite, because the ancients found that magnetite could attract many ferromagnetic minerals, so they thought it had maternal kindness, so they called it Cishi. This formula often refers to porphyry copper deposits. The development of porphyry copper deposits is closely related to oxygen fugacity, which is suitable for copper and gold mineralization in the early stage of mineralization. In the late stage, when oxygen fugacity is no longer suitable for mineralization, magnetite will appear. Therefore, when magnetite appears widely, copper, gold and other minerals are likely to appear in the lower part of magnetite.

Magnetite ore

If there is lead on top, there is silver on bottom.

Lead here mainly refers to galena, while silver is natural silver or silverite. Although the natural silver mentioned here is secondary, it is often associated with pyroxene and occurs in the oxidation zone of lead-silver deposits. The primary silverite is a common mineral in medium and low temperature hydrothermal deposits, which also develops galena ore. Galena and chalcocite are closely related in the process of mineralization, and they are often associated with each other. The ancients had a particularly profound understanding of this point. "lead is the mother of silver and silver is the essence of lead". Although the formation of the two may not promote each other, it is not difficult to see the close symbiotic relationship between the two ores.

Galena

Miao silver ornaments

There is red sand on top and gold on the bottom.

This prospecting formula is not suitable for today's prospecting. Dansha and natural gold usually exist in their own primary veins, and very few may have a symbiotic relationship. However, the ancients' research on the mineralization of mercury and gold was not mature. At that time, mercury deposits and gold deposits were dominated by placers, so placer deposits with symbiosis of mercury and gold appeared, so it was more accurate to look for deposits at that time according to this formula. Of course, from the current research, the Carlin type gold deposit also has the phenomenon of associated with natural gold and cinnabar, but considering that this deposit mainly produces fine natural gold, the technology of the ancients should not be enough to mine this type of deposit.

Dan sand vase

Placer gold

There are lead, tin and red copper under the mausoleum.

The mausoleum stone here is a relatively unfamiliar name to us, but it was introduced into greenstone in Taiping Imperial View Earth III, which was verified as malachite by later scholars. This formula applies not only to lead-based lead-zinc-copper polymetallic deposits, but also to tin deposits and chalcopyrite deposits associated with copper, lead and zinc. These deposits are rich in sulfides, chlorides and copper ions, so some malachite will be formed in the process of epigenetic weathering. Of course, the two situations of "there is tin under the mausoleum" and "red copper under the mausoleum" are also the experiences summed up by the ancients according to the actual prospecting phenomenon.

Malachite

Cassiterite

If there is silver on top, there is lead under it.

This formula seems to be the exact opposite of the third conclusion, but in fact it is also widely used in ancient mining. This relationship, which contains silver above and lead below, actually does not refer to the vertical distribution of two metallic minerals in an orebody, but to the spatial relationship between the tw