These nice stuff are not mine, unfortunately.
My friend CP collected these works of fine craft, all by the Feng father and son team. Some of the pieces really shows the characteristics of ivory.
All of these are seal sets including a case, the case cover, and the seal block inside. The small square boxes is to store the red mineral ink 硃砂 if the set is put to practical use. In China, and Chinese cultural spheres including Japan, Korea, and part of SE Asia, seal sets like these used to be very common People carry their personal seal for contracts, banking transactions, etc... In the mainland China, the seal still carry more weight than signature for legal documents.
For fine crafts like these, they are considered works of art and toys, not really craved as personal seal.
The cork is there to show the scale. Each Chinese character on cover and the seal block is less than 1mm! I couldn't read the characters easily.