Why the solution when pouring can differ in density at the same composition, water and temperature.
Gypsum is a natural material with a changing water-gypsum ratio. That is, to create a solution of normal density, different amounts of water are required, it depends on the rock and reservoir. Therefore, before pouring, it is necessary to test on a small amount of gypsum.
The range is from 50-60% water by weight of the gypsum
We recommend using high-strength alpha gypsum, there is no such problem with water, it is more expensive, but this is compensated by saving on marriage and losses in production.
Also, in production, first take a sample from the party.