Silica raft clusters

 

The floating formations in the image appear to be mineral precipitates. As the water cools and evaporates, silica precipitates out of the solution. If the precipitation occurs at the water’s surface, these silica deposits can form thin, floating crusts or “rafts.” These rafts often break apart and re-aggregate, creating the clustered appearance. The tan/brown patches could be iron oxides or other oxidised minerals, indicating areas where different chemical reactions have occurred.