Cape generally refers to sea ivory, which refers to the teeth of walrus in the Arctic Ocean, and can be carved as works of art, such as boxes and pendants. Sea ivory has a flat three-petal cross-section, mostly pale yellow and cream-colored, which is rougher than ivory and hippopotamus's teeth, and its core is crisp and close to ordinary bones.

Introduction to Cape Wan Wen:

In the literary world, it is often seen that the spacers, beads and pendants of some bracelets are made of what the seller calls "sea ivory", which is delicate and smooth with cloud-like "tooth marks" on the surface, which is very beautiful. However, it should be noted that this so-called "sea ivory" is not the ivory of walrus, but made of celluloid, which means it is synthetic.

Horn must be dyed green as jade. For this, players need to pay attention to avoid being ignored by sellers and regard cheap synthetic materials as precious natural materials.