Fairy Calcite XXL size from Morocco. Very nice for a collection.

Fairy stone calcite is a gray or beige stone with soft, smooth and very round shapes. This calcite species is formed in cavities filled with clay and sand in, for example, rivers, glaciers or sandstone rocks.

The mineral calcite (also called calcite) consists mainly of the salt calcium carbonate (CaCO3) and is one of the most common minerals in the earth's crust. Calcium carbonate arises because soluble calcium ions come into contact with CO2 (carbon dioxide forms a carbon ion if there is a positive ion in a solution). Calcium carbonate is a sparingly soluble salt, causing the CaCO3 formed to precipitate; this is done according to the following reaction: Ca2 + (aq) + CO32- (aq) - → CaCO3 (s) Calcite is a common constituent of sedimentary rocks, of veins and in deposits in hot springs and caverns in karst areas (like dripstone). It is the mineral that forms limestone and therefore the most common mineral of biological origin. Calcite is the main constituent of limestone, chalk and marble and it is also an important constituent of marl, limestone and limestone. Calcite is responsible for the chemical weathering of coagulation and metamorphic rocks, creating sedimentary rocks. Calcite is soluble under light pressure in CO2-containing water. During the fall in the air, rainwater absorbs the gaseous carbon dioxide, making it acidic. This acid rainwater is able to dissolve lime. In underground currents, this material can transport in solution until, after contact with atmospheric pressure, CO2 escapes and the calcite precipitates. This is how stalagmites and stalactites are formed in caves. In the past, the transparent Icelandic form of calcite, called Iceland feldspar, was used to produce Nicolprisms. Some researchers assume that the Vikings navigated at sea using crystals of this mineral, which can also accurately determine the position of the sun even in cloudy weather. Nowadays limestone is mainly used in construction as a building element, for the manufacture of lime and cement, while marble is used as building and ornamental stone.