Below you can find the At 15 on the modified mohs' scale this substance still has the highest hardness number Jeopardy Words Answer. The answer to At 15 on the modified mohs' scale this substance still has the highest hardness number has 7 letters. This clue belongs to the Physical science category and is part of Jeopardy Word Level 1016. If you scroll near the bottom you will find other clues and answers part of level 1016