Hi,
she was built as SANAI MARU in 1970 at Imai Zosen, Kochi, Japan.
Her IMO No. is 7019646.
Name change to MOUNT HORIZON apparently in 09.1979.
From Lloyd's Casualty Return 1980:
"Sailed from Guayaquil on 21st February for Philadelphia and
last reported E. of Miami in Lat. 25 06N., long. 79 07W.,
on 1st March and not since heard of."
Kind regards,
Weserphoto