Grab a large pot and mix the salt and water.
Bring the water to a boil.
While boiling, stir until all the salt has dissolved and salt crystals start to form on the side of the pot.
Remove from heat and let cool to room temperature.
Grab a large glass jar and place your duck eggs inside carefully. Make sure the eggs don't crack as you do this.
Slowly pour in the salt water until all the eggs are submerged.
Cover the container with the lid and leave it in a cool dark place for 3-4 weeks.
If you prefer less salty eggs, you can take out one egg to test after three weeks.
Boil the salted egg in water for ten minutes until it is hard-boiled.
Remove the shell and taste to see if it is salty enough to your liking.
If not, leave the eggs in the container for another week or two.
Remove the salted eggs from the salt water and store them in the refrigerator until they are ready for use in any of your dishes.