Hi Maria, stamped on the thread collar reads, T (surrounded in a circle which could either be the manufacturers mark or stand for Tungsten which is most likely) 120V25WJAPAN. The base I believe is North American as this exact base was sold together with a large medium base Santa Lamp in the late 1920s. Can't be sure of a date on the lamp as the Japanese were using colored glass in bulb manufacturing from early 1900s into the late 50s. Chances are it may have been a replacement to the large Santa Lamp originally sold with the base.
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