Below you can find the Gypsum has often been added to the portland variety of this to slow the hardening process Jeopardy Words Answer. The answer to Gypsum has often been added to the portland variety of this to slow the hardening process has 6 letters. This clue belongs to the Technology category and is part of Jeopardy Word Level 384. If you scroll near the bottom you will find other clues and answers part of level 384