Combine all the ingredients except zinc oxide in a pint-sized or larger glass jar.
Fill a medium saucepan with a couple inches of water and place on the stove over medium heat.
Put a lid loosely on the jar and place it in the pan with the water.
Shake or stir the jar occasionally to mix the ingredients as they melt.
When all the ingredients are completely melted, stir in the zinc oxide, and pour into whatever jar or tin you will use for storage.
Stir a few times as it cools to make sure zinc oxide is incorporated.
Store at room temperature or in the refrigerator to increase shelf life.