The phrase "small crystals" refers to tiny, solid objects that have a specific shape and structure. These crystals are typically very tiny and can be found in various forms, like salt or sugar. Full definition
The present data suggest that the ice is in the form of small crystals, comprising about 0.3 percent to 1 percent of the moon's rocky soil. (scientificamerican.com)
This process is not only slow and inefficient, but is extremely difficult or impossible for very small crystals. (sciencedaily.com)
In appearance, it's white with small crystals that are slightly larger than sugar. (naturalsweetrecipes.com)