There's a death certificate for Albert Martz that says he was the son of John Martz and Mary Savage. I think the informant was simply confused about the fact of Albert’s mother’s first name.

Albert was listed in the 1850 Census age 1 living with John and Harriet. Albert is designated P6c1a.

Albert was also with his parents in 1860 age 11. I cannot find him in 1870. In 1880, he was age 30 reported as the son-in-law of Samuel Keefer. Harry Martz age 2 was present. Harry must have been Albert’s son, so Samuel’s grandson — but he was reported as Samuel’s nephew.

His death certificate said he died 21 Dec 1910 and the informant “thought” he was about 64 years old.

Gearhart lists Albert Martz 1849-1910 at Penns Cemetery. The 1849 date conforms better to Census.