A Translucent or White Granular Form of Gypsum
This page is the CodyCross answer for the clue below from Space Exploration, Group 901, Puzzle 1 (Telescopes).
Question is: A Translucent or White Granular Form of Gypsum
and the answer is: ALABASTER
Word Meaning:
ALABASTER — A fine-grained white or lightly-tinted variety of gypsum, used ornamentally.
Definitions from Wiktionary.