Meng Shi (Lapis Stone)

Chinese Herb Actions

Chinese Herb Dosage

• What is the typical dosage of Meng Shi?

  Our record gives 6–10 g in decoction and 1.5–3 g as powder from one reference, and records no range from the other. As with other dense minerals, the powdered dose is far lower than the decocted dose, because a decoction extracts comparatively little from an insoluble rock while a powder is swallowed in full.

  • Decoction: 6–10 g.
  • Powder: 1.5–3 g — a substantially lower ceiling.
  • Form in practice. Much of the classical use is as a constituent of pills rather than as a decoction ingredient — Gun Tan Wan is a pill — which is why the powder figure matters.
  • Preparation (reference fact, not instruction). Commercial material is normally supplied already calcined; where the raw stone is used it is conventionally crushed and decocted ahead of the other ingredients.

  Reference information only, not a prescription. Our record attaches real contraindications to this herb — see cautions.

  Source: our own herb record (recorded ranges, including that one reference gives none). Reference only — not a prescription.

Chinese Herb Contraindications & Cautions

• Are there cautions for Meng Shi? Who should avoid it?

  Yes — our record contraindicates Meng Shi in pregnancy, in children, and in anyone with weak digestion or qi deficiency. That is a broader set of restrictions than most cough-and-wheezing herbs carry, and it reflects what this medicinal is: a heavy, downward-driving mineral used to force out phlegm that ordinary herbs have failed to move.

  • Pregnancy — contraindicated per our record.
  • Children — contraindicated per our record.
  • Weak digestion or qi deficiency — contraindicated per our record. A draining, descending mineral is the wrong direction for a depleted patient.
  • Short courses only. Materia medica practice restricts it to the acute stubborn-phlegm situation rather than ongoing use, and to the recorded dose ranges.
  • Not for ordinary coughs. This is not a general expectorant; the traditional indication is thick, hard, lodged phlegm and phlegm-fire patterns.
  • Professional supervision. Given the contraindication list, the pattern-specific indication and its mineral nature, this belongs in the hands of a qualified practitioner.

  Source: our own herb record (all four recorded contraindications). Neutral reference notes, not a safety guarantee.

Chinese Herb Toxicity & Overdose

• Is Meng Shi toxic? Does it contain heavy metals?

  Our record lists no toxicity for Meng Shi, and only one piece of published work bearing specifically on trace-element or heavy-metal content of this material was located. A chromatographic method coupled to inductively coupled plasma mass spectrometry was developed for determining hexavalent chromium in traditional Chinese medicines, and it was applied to Chloriti lapis (Qing Meng Shi) among its test materials, with satisfactory recoveries. That is a method-development paper — it establishes that hexavalent chromium is a recognised analyte worth measuring in this mineral, not that any particular batch on the market exceeds a limit.

  • What is documented for this material. Hexavalent chromium is an analyte of interest in Chloriti lapis, with a validated determination method available. Separately, animal work on Chloriti Lapis measured a broad panel of metal elements (iron, aluminium, magnesium, manganese, copper, zinc, tin, vanadium, cobalt, titanium, beryllium, lead) in plasma and lung tissue after administration — that study is about mechanism, not contamination limits.
  • What we are not saying. We are not importing generic claims that Chinese herbal medicines contain heavy metals. No published market survey quantifying heavy-metal content of Meng Shi was located, so none is cited.
  • Why it matters more for minerals than plants. A mined rock’s composition depends on the deposit it came from. That is the reason instrumental identification and fingerprinting methods for these materials exist at all, and it is the practical argument for tested material from a reputable supplier.
  • If contamination data specific to Meng Shi exists and can be produced, this section should be updated. We would rather record the gap than fill it with generalisation.

  Source: our own herb record (no toxicity recorded); hexavalent chromium determination applied to Chloriti lapis, PMID 26541101; metal-element panel in an animal model, PMID 34402294; identification methods per PMID 30079701 and PMID 22256753. Reference note only, not a safety guarantee.

Herb-Drug Interactions

• Does Meng Shi interact with medications?

  No herb–drug interaction studies for Meng Shi were located, and our record lists none. Nothing is asserted here that we cannot source. Two general points are worth stating as reference information rather than as documented interactions.

  • Mineral medicinals and drug absorption. Dense mineral powders taken by mouth are, as a class, a reasonable subject for spacing away from other oral medication. This is a general pharmaceutical principle, not a documented finding for Meng Shi.
  • Context of use. Meng Shi is generally taken within multi-ingredient formulas such as Gun Tan Wan, which contain strong purgative and heat-clearing herbs in their own right; any interaction question in practice concerns the whole prescription, not this ingredient alone.
  • Anyone taking prescription medication, and particularly anyone being treated for seizures or a respiratory condition, should have the whole formula reviewed by their prescriber and a qualified practitioner.

  Source: our own herb record (no interactions recorded) and our own formula record for Gun Tan Wan. Reference information, not clinical advice — no interaction study specific to this material was found.

Western / Biomedical Research

Chinese Herb Clinical Studies & Research

Provided as research context — a summary of published biomedical study, not a therapeutic or medical claim.

• Is there modern research on Meng Shi (Lapis Micae seu Chloriti)?

  Yes, but it is a small and almost entirely animal-based literature, and nearly all of it studies the chlorite form, Qing Meng Shi (Chloriti Lapis). There are no controlled human trials of this mineral that we could locate. What exists lines up unusually neatly with the two traditional indications — phlegm in the lungs, and seizures.

  • Lung / phlegm-heat (animal). A rat model of acute exacerbation of chronic obstructive pulmonary disease with a phlegm-heat presentation was created by smoke exposure combined with Klebsiella pneumoniae infection. After treatment with Chloriti Lapis, the profile of metal elements in plasma and lung tissue shifted measurably, and the treated group separated cleanly from the model group. A companion metabonomic study examined the lung tissue of the same model. Mechanistic animal work — not evidence of clinical benefit.
  • Seizures (animal). An intervention study of Chloriti Lapis in pentylenetetrazol-kindled epileptic rats has been published — directly relevant to the traditional “anchors the Liver, stops seizures” indication, and again preclinical only.
  • Mineral identity and quality control. X-ray diffraction, XRD Fourier fingerprinting and infrared spectroscopy have all been applied to distinguish Chloriti Lapis, Micae Lapis Aureus and Vermiculitum and to assess quality. This is where the mineralogical identification in the notes section comes from.
  • Analytical safety methods. A hexavalent-chromium determination method has been validated on Chloriti lapis (see toxicity).

  Why is Meng Shi calcined with saltpetre?

  Because the raw stone is too hard to use and the processed form is the one the classical texts specify. Standard preparation of Meng Shi involves calcining the crushed mineral together with saltpetre (nitre) at high heat, producing the material recorded as duan meng shi, calcined Meng Shi. Two purposes are given in the materia medica: the fired stone becomes brittle and can be reduced to a fine powder suitable for pills, and the processed form is held to be the more effective and better-tolerated form for internal use. Where a classical formula specifies Meng Shi — Gun Tan Wan among them — the calcined material is what is meant.

  This is stated as reference fact only. No method, proportions, temperatures or procedure are given here, and none should be attempted; processed material is supplied by the pharmacy already prepared.

  Sources: PMID 34402294 metal elements in an AECOPD rat model; PMID 34467705 lung-tissue metabonomics in the same model; PMID 30080018 pentylenetetrazol-kindled epilepsy model; PMID 30079701 X-ray diffraction identification; PMID 22256753 XRD Fourier fingerprint; PMID 15307681 infrared analysis; PMID 26541101 hexavalent chromium determination. Calcination with saltpetre per published materia medica and pharmacopoeial processing descriptions, cross-referenced against multiple online sources. Research context, not a therapeutic claim.

Chinese Herb Notes

• What is the difference between Qing Meng Shi and Jin Meng Shi?

  They are two related but distinct mineral materials sold under the shared name Meng Shi, and our site currently holds them in a single record. Qing Meng Shi (青秆石, “green meng shi”) is the chlorite-schist material, pharmaceutically Chloriti Lapis. Jin Meng Shi (金秆石, “gold meng shi”) is the golden mica-schist material, pharmaceutically Micae Lapis Aureus. X-ray diffraction analysis has traced Chloriti Lapis to biotite schist and good-quality Micae Lapis Aureus to vermiculite biotite schist, and the two are distinguishable by instrumental fingerprint — which is exactly why identification methods for them have been developed.

  • Qing Meng Shi — Chloriti Lapis, chlorite/biotite schist, greenish-grey, the material most of the published pharmacological work has actually used.
  • Jin Meng Shi — Micae Lapis Aureus, gold-flecked mica (vermiculite biotite) schist.
  • Vermiculitum is a third, separate mineral medicinal that is sometimes confused with these; its source minerals are phlogopite and vermiculite phlogopite.
  • How they are used. Both are used for the same broad indication — driving down stubborn phlegm — and references differ on whether one is preferred. Where a formula source specifies which, that specification should be followed.

  Note on our record: we hold one entry for Meng Shi, not two — there is no separate Qing Meng Shi record on the site. That entry mixes the two: the display name and slug are the generic Meng Shi, the alternative-names field lists both Jin Meng Shi and Qing Meng Shi, the Latin Lapis Micae seu Chloriti covers both, but the Chinese characters and the tone-marked pinyin are specifically those of Jin Meng Shi (金秆石, jīn méng shí). This is worth an owner decision — either a single combined entry with both names in the title, or a split into two records. The identity fields are left unchanged pending that decision.

  Source: our own herb record (single entry, its Chinese, pinyin, Latin and alternative names); mineral identification by X-ray diffraction per PMID 30079701; instrumental differentiation per PMID 15307681 and PMID 22256753. Cross-referenced against multiple online sources.