MATERIALS

lime_cycle After processing, products derived from limestone have the unique ability to return to their original chemical form. Lime starts from rock form and goes back again to the state of stone, after a series of events that transform it, eventually recreating its natural mineral essence, without affecting its durability and permeability. Lime mortars are derived from limestone. When limestone is heated, it breaks down to form quicklime and releases carbon dioxide. Quicklime reacts with water to form calcium hydroxide, a process also known as slaking or hydrating. Slake lime is mixed into a thick slurry with sand and water to form various kinds of mortars for building purposes. When masonry has been laid the slaked lime in the mortar slowly begins to react with carbon dioxide to form limestone. The reabsorption of carbon dioxide from the atmosphere by the calcium hydroxide is time consuming and can take many years to form calcium carbonate (limestone). This process is known as ‘The Lime Cycle.’

Quicklime is a white to gray solid with a crystalline structure, and the product of calcination of limestone. It is highly reactive with water, generating considerable heat in the hydration process. The primary forms of Quicklime are:

high calcium quicklime derived from limestone containing up to 5% magnesium carbonate
dolomitic quicklime derived from limestone containing up to 35% of magnesium carbonate
hydraulic lime is derived from clay rich in silica, aluminum and iron and gets harder with the addition of water. It has more impurities and is less white.

	Environmental / Ecological Lime gives off less carbon dioxide during the manufacturing process than other materials such as cement and it reabsorbs carbon dioxide over time as it sets Recyclable and biodegradable Essential in the building of any natural house Pigments used to provide color to plaster are mineral-based and all natural, avoiding the use of chemical additives
	Durability / Efficiency Allows the building to “breath” Water can escape by evaporation/transpiration avoiding condensation Water resistant Provides good thermal and acoustic insulation Lime continuously pulls moisture from the air in the setting process which has a cooling effect in the summer (osmosis). In the winter, the process is reversed. Self healing: the flexibility of high calcium lime plaster and stucco withstand cracking from shrinkage and settling. It moves with the building. Non-combustible: provides a thermal skin that slows down fire infiltration to flammable building components
	Health The permanent alkalinity of lime inhibits the development of bacteria and mold growth Suitable for people with allergies Does not produce toxic gases or odors; Avoids efflorescences (crystaline deposits on surfaces of masonry or concrete) due to the absence of soluble salts in the material, preserving adjacent materials frequently affected by this like wood, iron, stone or brick
	Aesthetics Lime finishes are beautiful. The double refraction of light through calcite crystals gives unique aesthetic combining a soft texture with luster that has a beauty on its own. It can rapidly develop a rich patina which has a glowing translucent quality