There are a few different ways to separate calcium carbonate from sand. One common method is to use a process called froth flotation. In this process, the sand and calcium carbonate are mixed with water and a foaming agent. The foaming agent causes the calcium carbonate to float to the surface of the water, while the sand sinks to the bottom. The calcium carbonate can then be skimmed off the surface of the water and collected. Another method for separating calcium carbonate from sand is to use a process called gravity separation. In this process, the sand and calcium carbonate are mixed with water and then allowed to settle. The calcium carbonate will settle to the bottom of the water faster than the sand, so the two materials can be separated by simply pouring off the water. Finally, calcium carbonate can also be separated from sand using a process called magnetic separation. In this process, the sand and calcium carbonate are mixed with a magnetic material. The calcium carbonate will be attracted to the magnetic material, while the sand will not. The calcium carbonate can then be removed from the sand using a magnet.