Exodus 30:34-38

Then the LORD said to Moses, “Gather fragrant spices—resin droplets, mollusk shell, and galbanum—and mix these fragrant spices with pure frankincense, weighed out in equal amounts. Using the usual techniques of the incense maker, blend the spices together and sprinkle them with salt to produce a pure and holy incense. Grind some of the mixture into a very fine powder and put it in front of the Ark of the Covenant, where I will meet with you in the Tabernacle. You must treat this incense as most holy. Never use this formula to make this incense for yourselves. It is reserved for the LORD, and you must treat it as holy. Anyone who makes incense like this for personal use will be cut off from the community.”