5D Library › Crystal Piezoelectricity, Iron-Nickel Meteorites and Photobiomodulation · 中文
Chapter 7 The Classics of Stones
Observation before theory
Chinese scholars recorded stones, metals and minerals with great care long before there was any theory of crystals or of meteorites. Read beside the physics of the earlier chapters, three kinds of record stand out: an eyewitness account of a meteorite fall, a connoisseur’s catalogue of stones that notes how they sound when struck, and the mineral entries of the materia medica.
A star that fell at Changzhou
Source text
治平元年，常州日禺时，天有大声如雷，乃一大星，几如月，见于东南。……乃得一圆石，犹热，其大如拳，一头微锐，色如铁，重亦如铁。(沈括 1088)
In the first year of the Zhiping reign [1064], at Changzhou, in the late morning, there was a great noise in the sky like thunder, and a great star, almost as large as the moon, appeared in the south-east. … They found a round stone, still hot, as large as a fist, slightly pointed at one end, the colour of iron and as heavy as iron.
(Shen Kuo, Brush Talks from Dream Brook, chapter 20)
Shen Kuo’s account, which the omitted lines fill out, contains every element a modern meteoriticist would ask for: the time and place; the sound, which came in three detonations; the fireball; the fall itself, in the garden of a family named Xu in Yixing county, where it burned the fence; a small, deep hole; a glowing object at the bottom that cooled slowly; and, when dug out from about three chi down, a fist-sized stone, still warm, iron-coloured and iron-heavy. He also records that the prefect sent the stone to the Jinshan temple at Runzhou, where it was kept in a box and shown to visitors. “As heavy as iron” suggests an iron or a metal-rich meteorite, though from a description alone one cannot be sure.
Note
A phrase sometimes attributed to Shen Kuo, that smiths treasured meteoritic iron from Leizhou, could not be found in the Brush Talks. His own discussion of objects said to have “fallen with thunder”, the “thunder axes” and “thunder wedges”, concerns axe- and wedge-shaped objects found after thunderstorms, not meteorites. This book quotes only the Changzhou passage.
Stones that ring
Source text
宿州灵璧县地名磬山，石产土中……清润，扣之铿然有声。(杜绾 1133)
At a place called Chime Mountain in Lingbi county, Su prefecture, the stones come out of the earth. … [Cleaned,] they are clear and smooth, and when struck they ring with a clear, resonant sound.
(Du Wan, Stone Catalogue of Cloudy Forest, “Lingbi stone”)
Du Wan’s twelfth-century catalogue describes more than a hundred kinds of stone prized by scholars for their shapes, colours and textures. It repeatedly records how a stone sounds when tapped: the Lingbi stone rings, while the entry for Qingzhou stone notes that it “makes no sound when struck” (扣之无声). The very place name, Chime Mountain, recalls the stone chimes (磬) of ancient Chinese ritual music. In the language of Chapter 1, a stone that rings is one with low internal damping, a high quality factor: once struck, it keeps vibrating for many cycles. That is the same property, on a far smaller scale, that makes a quartz resonator keep time.
Hypothesis · not established
Not established. The Song connoisseurs’ distinction between ringing and silent stones corresponds to a measurable difference in mechanical quality factor. The hypothesis predicts that for samples of the kinds Du Wan calls ringing, such as Lingbi stone, the ring-down time after a light tap, measured with a microphone, is much longer relative to the period of the sound than for kinds he calls silent, such as Qingzhou stone, measured on pieces of similar size. It would be refuted if, across several pieces of each kind, the quality factors overlapped substantially.
Minerals in the materia medica
Source text
白石英，味甘微温。主消渴，阴痿不足，咳逆，胸鬲间久寒，益气，除风湿痹。久服轻身长年。(孙星衍、孙冯翼 辑 1799)
White quartz: sweet, slightly warm. It governs wasting thirst, impotence and deficiency, cough with counterflow, long-standing cold in the chest and diaphragm; it boosts qi and removes wind-damp impediment. Taken for a long time, it lightens the body and lengthens the years.
(Shennong’s Classic of Materia Medica, upper grade)
Source text
慈石召铁。(吕不韦 等, n.d.)
The loving stone calls iron to it.
(Master Lü’s Spring and Autumn Annals, “Jingtong”)
The Shennong Bencao Jing places white quartz among its “upper grade” substances, those thought suitable for long use, and lists the lodestone, cishi, “the loving stone”, as a remedy for joint pain and deafness. The image of a stone that “loves” iron and draws it to itself, recorded in the third century BC, is one of the earliest descriptions of magnetic attraction anywhere. Li Shizhen’s Bencao Gangmu of 1578 gathers these and many other minerals in its section on metals and stones, including rock crystal (水精), white and purple quartz and lodestone, with the earlier commentaries (李时珍 1578). We have not found an entry in it that can be identified with tourmaline; the name bixi (碧玺), under which tourmaline was prized at the Qing court, appears in later sources.
Note
These are historical records of what earlier physicians believed, not evidence that the minerals work, and not advice. Several traditional mineral medicines are toxic, and fine quartz dust causes silicosis when inhaled. Nothing in this chapter should be taken as a recommendation to ingest, inhale or apply any mineral.
References
Fan, Y. (2026). Crystal Piezoelectricity, Iron-Nickel Meteorites and Photobiomodulation: Alpha-Quartz, Tourmaline Pyroelectricity, Widmanstätten Diffusion and Near-Infrared Cytochrome c Oxidase in Solid-State Physics and Biophotonics [晶体压电性、铁镍陨石与光生物调节] (Version 1.0.0). 5D Library. https://doi.org/10.5281/zenodo.23698498 · Licensed under Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0).