"DATE A TOMBSTONE" One way to figure out the era your ancestor was buried is to examine the material from which the tombstone is made. If your ancestor has a stone made of slate or common fieldstone (except wood used by pioneer) chances are the stone dates from 1796-1830. If the stone is flat topped hard marble, dates are about 1830-1849. If your mystery stone is round or pointed< soft marble with cursive inscriptions, look for a date of 1845-1868. Masonic four-sided stones began in 1850< and are still in use today. Pylons, columns and all exotic-style monuments are usually dated 1860-1900. Zinc monuments date from 1870-1900. Granite, now common, came into use about 1900.