Hendrik Keyzer was born in 1716. He was the son of Lammert and Lena Walschot. In 1739 he married Grietje Donker. They got one son, Petrus Lambertus, who became a silversmith too. Eight years later Hendrik was registered as a silversmith in Amsterdam. He is known to have produced objects for table services. Hendrik Keyzer died in 1781.
For comparative literature:
Citroen, K.A., Amsterdamse zilversmeden en hun merken, Amsterdam, 1975, p. 67.