My great-great grandfather was Jon/John (possibly Jonathan) Tonks. He was supposedly born in London, England. According to familysearch.org he was born in San Francisco, California. He was a geologist who traveled to a mining town called Tayoltita, in the state of Durango in Mexico. He worked for a company called Luismin. He married my g-g-grandmother Cleofas Troncoso in 1897 according to familysearch.org She was born about 1876 in San Dimas, Durango, Mexico.
Jon died in the early 1900's, before 1915. Cleofas died about 1928. They both died in San Dimas, Durango, Mexico.
They had 5 children: Luis Tonks Troncoso, Frutouso Tonks Troncoso, Percy Tonks Troncoso, Delfina Tonks Troncoso, and Ana Tonks Troncoso. I have more information on my great-grandfather and his siblings but have been stuck for 10 years not able to find any info past my g-g-granparents.
If you are missing a Jon Tonks or Cleofas Troncoso please let me know-Thanks, April Pimentel firstname.lastname@example.org