Glass is a material made primarily from sand. Silica or quartz type of sand is the preferred material in making glass. A small portion of limestone and soda ash is also needed to mix with silica sand to make glass. The purer the silica sand, the clearer will be the glass material output. In case iron is present in the mix, the resulting glass will have a greenish color. In making glass, extremely high temperatures are necessary in order to form the various shapes and sizes of glass.
Natural glass is said to be found after a volcanic eruption. The very high temperature of the eruption is basically enough to melt whatever sand is present in a volcano and transform it into a glass-like material. With the origin being a volcanic eruption, natural glass is expected to have a burned or black color. This original glass material was said to be used by ancient people as tips for their spears and other weapons. As time evolved, people have eventually found a way to create glass in different sizes, shapes, and color.
Under extremely high temperature, glass components like sand, limestone, and soda ash will basically melt turning the mixture into a type of liquid. This liquid can then be converted back to a solid form as the temperature decreases. At room temperature, the glass material that people are familiar about is in a solid state. The origins of glass though are one in a liquid state because of the melting of sand and other materials. As the sand melts under extreme heat, it can then be manipulated to be formed into different sizes and shapes. This is the part that modern glass-making involves blowing air into the melted liquid to form various shapes and sizes. Once the temperature drops, the glass material will then assume a solid state. Jars, glasses, and figurines for example all started as liquid or melted glass and were later manipulated to become another shape or size as the material reaches room temperature.