Pteria martensii.  珍 珠 Zhēn zhū   Mother of pearl, Oyster pearl   

Nature- cold   FLAVOR: Sweet, salted. CHANNELS: Heart, Liver.  
FUNCTIONS
GROUP: Calm Spirit- Strong
1. Calm down Spirits.[1]
2. Calm down Liver, calm down convulsion, calm down spirits.[1]
INDICATIONS
1. Epilepsy, convulsion in children, palpitation, insomnia.[1]
2. External applications for corneal opacity, sore throat, swelling of tongue, ulcer that fails to heal for a long time.[1]
PREPARATIONS: Pearl 0.3-1 g.[1]


珍珠母 Zhēn zhū mǔ Mother of pearl oyster shell- collected the whole year round.  
Pteria matensii is mainly produced from the coastal areas of Hainan, Guangdong and Guangxi of China.
Hyriopsis cumingii and Cristaria plicata are widely produced from lakes rivers and marshes in China.
Nature- cold  FLAVOR: Salty  CHANNELS: Liver, Heart
FUNCTIONS
Pacify Liver and subdue Yang, clear Liver Heat and improve vision, suppress Heart and induce tranquilization.[2]
INDICATIONS
1. Liver yang hyperactivity.[2]
 CONTRAINDICATIONS Cold deficiency of the Spleen and Stomach because its Cold Nature may injure the Stomach.[3]
COMPARISON
It is similar to Shi jue ming in pacifying Liver, subduing yang and clearing Liver Heat, but its action is weaker than that of Haliotis funebris- Shi jue ming. It is good at calming Heart and inducing tranquilization to enter Heart channel. So it is mutually reinforced by Shi jue ming.
PREPARATIONS:
Ingested 15-30 g in decoction, or 1.5-3 g powder.[3]
The meat is removed and cleaned with water and dried in the sun. The best quality are those that are big with clear white color.
References
Inner Path can not take any responsibility for any adverse effects from the use of plants. Always seek advice from a professional before using a plant medicinally.
Constituents
Research

Pearl and mother-of-pearl powder in health-care. [Article in Chinese]
Cao G, Xu Z, Wei H, Yao S, Liu Y.
Abstract
Based on pharmacological studies in files, mice and rats, the powder of sea pearl (Pteria martensii), mother-of-pearl and freshwater pearl has been proved to have tonic, anti-aging and anti-radiative actions. The effect of the sea pearl and mother-of-pearl powder is higher than that of freshwater pearl powder.
PMID: 9772634 Zhongguo Zhong Yao Za Zhi. 1996 Oct;21(10):635-8 inside back cover. ncbi.nlm.nih.gov