A friend taught me to put 3 tablespoons of Crisco in each quart jar of my lard, while it was very hot, stir it good and there will be enough preservative in the Crisco to be sure your lard keeps, in a cool dark place.
It is what they were taught to do during WW2, I did it and it worked for me on pork lard.
Liquid crisco or solid stuff?