A spoon is a measure of volume. Different substances have different densities so that the same volume of two substances can have very different masses.
1 TSP which is 1 tea spoon
1million equal to how much?
If you want to measure the length of a spoon, you'd use centimeters or millimeters. If you want to measure its capacity (how much it could hold), you'd use milliliters.
One gram is equal to one gram.