: The particles (like fused quartz or hydrogel beads) must have a refractive index identical to the liquid filling the gaps to become truly transparent.
A "proper" transparent soil must balance optical clarity with the physical needs of plants or engineering models:
Transparent soil is rarely sold as a finished retail "bag." Instead, users typically purchase the raw components based on their specific research needs: Best for long-term root observation and microbial studies.
: For plant studies, it must be non-toxic and allow for the transmission of oxygen, water, and nutrients.
: It must resist collapsing under its own weight and provide enough "grip" for roots to anchor effectively.