Brand: J.J. Rehbach
Made in: Germany
Not sure if that is black lead or exactly what??
Founded in 1820, J.J. Rehbach was also known as “Key Pencil Co.” After going bankrupt in 1934, the company merged with another German pencil brand, Argona, but continued making pencils under the Rehbach name for some time. The advertising stamp below shows the crossed key motif and the company’s factory in Regensburg, Germany. (Photo credit: buchfreund.de)