There were both Caldera and Calderon in Zacatecas. You did not post any approximate dates other than Feliciana Caldera/Calderon born abt 1835 died 1935. Don't put too much stock into ages put on headstones. I have not found many from the 1850's or so that were correct.. If your family was from Jerez there are lots of missing records when doing research. I did post all my research for the Caldera lines on Ancestry.com so I wish you luck in your search for family.