Concha Arcae
Source
The shell of Arca granosa L., A. inftata Reeve, A. subcrenata Lischke,
family Arcidae.
Characteristics
Shell fan-shaped, convex at the back, top protruding and involute, 3-9
cm long. Outer surface grey-yellow to 
white,
with 20-50 striae spreading from the top toward the edge, protruding or
smooth at the striae, glabrous or with residual hairs. Inner surface milky
white and smooth. Prepared as fine powder for use. Sweet and salty in
taste, mild in nature, and attributive to lung, stomach, liver and spleen
channels.
Indication
1. Eliminate phlegm and remove blood stasis, soften hard lumps and dispetse
nodes: For subcutaneous nodule, scrofula and abdominal mass.
2. Antacid and alleviate pain: For stomachache with hyperchlorhydria,
used together with Radix Glycyrrhizae.
Administration
Decoction:
9-30g (crushed before decocting).
Powder: 3-6g bid or tid.