When were silver certificates marketed?

Silver certificate (and all other bills, for that matter) are circulated rather than marketed. "Marketing" means to put up for sale.

Silver certificates were introduced in 1878. They were backed dollar-for-dollar by an equivalent amount of silver on deposit with the Treasury. They were discontinued in the early 1960s when the price of silver had to be deregulated, which meant there was no longer any way to keep a fixed link between the bills' values and silver metal's value.

Silver certificates were never withdrawn or demonetized. The Treasury simply stopped redeeming them for silver. The bills gradually disappeared from circulation as they wore out or people saved them as keepsakes.