IshEz 49(21) :ܩܪܘܣܛܠܘܣ܃ ܐܝܟ ܕܐ݁ܡܪ ܒܣܝܠܝܘܣ܃ ‍{‍ܚܘܪܘܬܐ‍}‍/ܚܘܪܬܐ/ ܗܝ ܘܡܢ ܓܠܝܕܐ ܕܡܬܩܫܐ ܗܘܝܐ܂ ܘܓܘܢܗ݀ ܐܝܟ ܓܘܢܐ ܕܡ̈ܝܐ ܨ̈ܠܘܠܐ‏ : crystal: as PN says, it is whiter than hardened ice, and its color is like the color of pure water
See the entire entry for qrusṭelāws n.m. crystal