July 15, 2010

limestones

             Earth is very rich with minerals. One of its that found to be quite a lot is limestone. The potential of limestone in Indonesia is very large and spread almost evenly throughout the Indonesian archipelago, such as in Padalarang (West Java), Central Kalimantan (Waringin City West, North Barito, Joyless Kingdom), Palimanan (Cirebon regency, West Java) and other areas. Limestone contained in various kinds of nature, such as: calcite (CaCO3), dolomite (CaCO3.MgCO3), magnesite (MgCO3), siderite (FeCO3), ankerit [Ca2Fe (CO3) 4], and aragonite (CaCO3) that chemical composing the same but different in the calcite crystal structure.

            Limestone (calcium carbonate CaCO3) when burned with a certain temperature (> 900o C) will produce carbon dioxide (CO2) and becomes calcium oxide (CaO). Calcium oxide if mixed with a little water will be a powder of lime, or hydrated lime (calcium hydroxide, Ca (OH2). This process is called the action of water (slaking) and limestone known as hydrated lime. Hydrated lime if left in open area in long period, it’s water content will be lost and react with carbon dioxide in the air and became a calcium carbonate.