Coprecipitation is a phenomenon where a solute that would normally remain dissolved in a solution precipitates out on a carrier that forces it to bind together, rather than remaining dispersed. This can occur in nature and in lab settings, and is sometimes actively facilitated, while in other cases it is an undesirable chemical reaction. In environmental remediation in particular, coprecipitation can be an extremely useful tool for sampling, purifying solutions, and cleaning up environmental hazards.