Hi Tom,
Namiki decorated items are signed in kanji characters which clearly identify the work to be that of the Namiki company, and also identifies the individual artist. I'm attaching an example - from the back of the compact with the goldfish decoration. Kanji characters are written vertically from top down. On the right, the three characters say Namiki-kan. To the left of these are two characters in gold which give the artists name, and beneath this a red seal, a pictograph artists' signature. Collectively, this is known amongst collectors as the 6-character signature, though sometimes the artists name can be one character only, so there are 5 characters. Some of the earliest Namiki pieces are unsigned, others just have the red seal. After 1938, the Namiki signature changed from "Namiki-kan" to "Kokko-kai", providing a milestone for dating.
The modern day Namiki company (Pilot) still produces and sells lacquer work - mostly pens, which command outrageous prices, and they still use the same 6-character signature. I fear this is probably more information than you wanted! But I'm passionate about collecting this stuff!

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