Below you can find the Though usually black this volcanic glass is also found in red brown & mottled varieties Jeopardy Words Answer. The answer to Though usually black this volcanic glass is also found in red brown & mottled varieties has 8 letters. This clue belongs to the Science category and is part of Jeopardy Word Level 1102. If you scroll near the bottom you will find other clues and answers part of level 1102