Pumice stone is typically used as an abrasive these days thanks to its stronger performance on getting rid of dark, hardened, and ugly dirt or stains on bathtub, toilet bowl, or any other hard surfaces. Most importantly, it causes little damage to the finish when scrubbing and cleaning, which is also the very reason why pumice stones are widely used for feet to remove calluses or exfoliate skin. However, it is very difficult to imagine that pumice is also a Chinese herb, which is called Fu Hai Shi, literally translated as the stone that floats in the sea, and good at removing old phlegm and palpable abdominal mass.
What is a pumice stone?
Pumice rock refers to the hardened foam of lava, which forms during volcanic eruption. It mainly consists of cellular volcanic glass, occasionally with a small amount of crystalline minerals. But its chemical constituents are similar to rhyolite, mainly including SiO2, Al2O3, K2O, and so on.
When it comes to Traditional Chinese medicine (TCM), Fu Hai Shi has a broader meaning, including pumice (Fu Shi) and the dried skeleton of Costazia aculeata Canu et Bassler or Costazia costazii Audouin (Shi Hu), which mainly refers to the skeleton of Porites nigrescens and sometimes a few species of Acropora.
Pumice stones are in the shape of irregular lumps, and slightly oblateness or oblong. They are not of uniform size and with a slightly flat base. They are off-white or pale yellow and with many small pores. They are hard and brittle, easily broken, and with rough cross section. They are so lightweight that they can float in the water. They have a slightly fishy odor and slightly salty flavor. Medicinally the preferred one should be intact, lightweight, off-white, and with globular branches.
Pumice stones health benefits
Natural pumice stone is generally made of silicate of aluminum, potassium, and sodium, as well as chlorine, magnesium and other substances. And the chemical constituents of Shi Hu are mainly CaCO3 and a small amount of magnesium, zinc, iron, aluminum and other elements.
Modern pharmacological actions
1. Clinical studies showed that this herb could promote the excretion of urine;
2. It can eliminate bronchial secretions;
3. It can reduce inflammation.
How to use a pumice stone in herbal formulas?
On the basis of TCM theories, it is salty in taste and cold in properties. It covers meridians of lung and kidney. Its basic functions are clearing lung and eliminating phlegm and softening hardness to dissipate stagnation. Primary pumice stone uses and indications include phlegm-heat cough, goiter and tumor, abscess, and so on. Recommended dosage is from 9 to 15 grams in decoction, or in powder or pills. In terms of using a pumice stone to its greatest health benefits, here are some proven experiences from those famous TCM herbalists.
Hai Fu Shi Hua Shi San
This formula comes from Yi Xue Cong Zhong Lu (Medicine for the Large General Population). It is an important formula for asthma in children, all wind-damp cough, dryness-heat cough, asthma due to excessive phlegm, and more. Other herbal ingredients are Hua Shi (Talcum Powder), Xing Ren (Apricot Seed), Bo He (Mentha), and Bai Bu (Stemona Root).
Hai Jin San
Hai Jin San comes in two different versions from Ren Zhai Zhi Zhi Fang (Effective Recipes from Renzhai House). The first one, combining with Gan Cao (Licorice Root), is a formula mainly designed for bloody stranguria and difficulty and pain in micturition. The second one is mainly formulated for hernia and constriction of the penis and sebaceous cyst on penis shaft. Other herbs are Mu Tong (Akebia Caulis), Deng Xin Cao (Rush Pith), Chi Fu Ling (Sclerotium Rubrum Poriae Cocos), and Mai Men Dong (Ophiopogon Tuber).
Shen Xiao San
Shen Xiao San comes from Lei Zheng Pu Ji Ben Shi Fang (Classified/Indexed General Treatment formulae). This is a prescription exclusively designed for thirst and drinking water all the time. Other ingredients are Ge Fen (Clam Shell Powder), Chan Tui (Cicada Moulting), and Ji Yu Dan (Maesa perlarius).
Qi Lao Dan
Qi Lao Dan, Fu Hai Shi (pumice) and Mo Yao (Myrrh), is from Pu Ji Fang (Prescriptions of Universal Relief). It is usually used for boils, carbuncle on the back, and malignant sores.
Mo Yao San
Mo Yao San is also from Prescriptions of Universal Relief. This is a prescription that is basically for pus under the ear. Other two herbs are Myrrh and She Xiang (Navel Gland Secretions of Musk Deer).
Potential pumice stone side effects and contraindications
In terms of TCM, pumice stone is inadvisable in case of deficiency-cold cough.