Rawhiti Cave become increasingly finer deeper down into the cave. A short walking track leads halfway down into the cavernous opening to a viewing platform. The diverse twilight-zone flora near the entrance of Rawhiti Cave makes this cave nationally significant. Over long periods of time, plant growth on the cave formations causes them to grow towards the sunlight as more calcium carbonate is deposited regularly on top of the plant growth. This phenomenon, called phytokarst, is most evident on the larger stalactites near the cave entrance, which are strongly curved outwards due to the heavy moss and fern growth on their sunlit
Calcium iodide in the air, liberating iodine, which is responsible for the faint yellow color of impure samples. Calcium iodide Calcium iodide (chemical formula CaI) is the ionic compound of calcium and iodine. This colourless deliquescent solid is a salt that is highly soluble in water. Its properties are similar to those for related salts, such as calcium chloride. It is used in photography. It is also used in cat food as a source of iodine. Henri Moissan first isolated pure calcium in 1898 by reducing calcium iodide with pure sodium metal: Calcium iodide can be formed by treating calcium carbonate, calcium