Questions, answered plainly.

It is a personal mark. Artists use one as a 落款 to sign their own work; writers and makers use one to mark what is theirs; it authenticates a certificate. It is a thing you press, and the impression is your name in a form nobody else has.

No. This is an artist's seal and a personal mark — it is not a registered 実印, and it should not be relied on as a signature or as legal identification anywhere. If you need a registered seal for official use in Japan, that is a different object obtained through a different process.

鳥虫篆 — bird-and-worm seal script — is an ancient ornamental form of Chinese seal script whose strokes resolve, on close looking, into birds in flight and insects at rest. 和風鳥虫篆, the Japanese-style form, is Tempoo's own invention. No one carved it before him.

About three months from payment. He carves one at a time, by hand, and the draft stage waits on your approval before anything is cut.

Not once the order is placed. The work is made only for you and begins immediately, so the order is final from that point. If you are unsure, the draft is the way to begin — you can commission the drawing alone first.

He works in 青田, 寿山 and 巴林. Master's choice is the usual answer and the best one: he picks the stone that suits the characters. Stones supplied by the customer are not accepted.

The seal, the first impression pulled by his own hand, a certificate of authenticity hand-stamped with his 落款, a serial number recorded from 001, and a wooden box.

Yes. A device and a name in one seal is a form he carves often. Describe what you have in mind in the motif field of the request, or leave it to him.

Say what you will use it for and he will advise. The sizes on the request form are shown in proportion to each other; exact dimensions are confirmed with you before carving.

Yes, tracked and worldwide. Shipping overseas is billed separately from the piece, and any import duties are the recipient's.