When I was in the Navy - over in Sardinia - we would get replenished by another ship about every 3 months. I remember getting cases and cases of refigerated eggs - maybe 40 dozen to a case - in waxed/sealed cardboard boxes. We ate them every day and they were fine right up till we got new ones. Who knows how long it took to get them to us from the time they were layed.
As for the sodium silicate; wasn't that the stuff they poured into the oil to wreck them beyond repair during the Cash for Clunkers program?