Terms & Tools: Lime
alluvium
Clay, silt, or gravel carried and deposited by a river or other running water. Typically made up of fine particles of silt and clay and larger particles of sand and gravel.
attapulgite
A magnesium aluminum silicate clay of very fine particle size. Has needle-shaped crystals. Also known as palygorskite or Fuller's Earth, it occurs naturally near Attapulgus, Georgia.
calcareous
Lime-containing
calcining
The process of controlled burning, of calcium carbonate (CaCO3) to drive off CO2 in order to create quicklme (CaO). Over burning the lime will melt the material thereby decreasing surface area. Correctly low fired lime is more coral-like & aerated, creating much more surface area, which is preferable.
calcite
A carbonate mineral and the stable form of calcium carbonate. Calcite is the main mineral component in limestone and is found in the shells of clams and oysters. When calcium carbonate percipitates out of water it becomes calcite.
calcium carbonate (CaCO3)
Chemical compound commonly known as limestone, one of the steps in the lime cycle. Burned at a {{specific temperature}} for {{a set amount of time}} it will create quicklme (CaO), and slaked with water it will create hydrated lime [Ca(OH)2]
calcium chloride (CaCl2)
A salt created by reacting calcium carbonate (limestone) with hydrochloric acid (muriatic acid) commonly used as a de-icing salt because of its deliquescent nature, which allows it to keep water in a liquid state.
calcium oxidide (CaO)
Chemical compound commonly known as quicklime or lump lime; one of the steps in the lime cycle. The compound is created when calcium carbonate (CaCO3) is calcined. Calcining causes CO2 to separate from the calcium carbonate compound, leaving CaO.
carbonation
When the lime (calcium hydroxide) in mortar or plaster is changed into a carbonate. Occurs when lime reacts with carbon dioxide from the air, releasing water through evaporation and forms calcium carbonate.
cementitious bond
In lime plastering or pointing, it is the intimate bonding of calcium hydroxide and water that is achieved through pressure. Failure to get sound cementitious bond between layers of plaster or mortar leads to delamination or two separate unconnected lifts.
deliquescent
The property of becoming liquid on exposure to air or having the ability to pick up moisture up from the air, commonly attributed to salts that continue to remain wet and move through masonry walls in the wet state as the crystals continue to grow in size.
efflorescence
Chalky residue deposited on the surface of masonry. After moisture in masonry is drawn to the surface by capillary action and the water has evaporated, concentrated powdery compounds such as salts or calcite are left on the surface. Often caused by chemical reactions of masonry components with chlorine in municipal water or acidic/basic cleaning solutions, all of which create salts which then deposit onto the surface.
glauconitic
Glauconite is a greenish mineral of silicate hydrate. Often found in sand or aggregate deposits. Its softness can create problems: when a joint is slicked glauconite breaks down and acts as a pigment, causing joints to become a spotty green.
grout
A thin mortar, with small aggregate particles. Sometimes dispensed into mortar joints with a grout gun.
hydraulic
Describes a material that sets in or under water. Once water is added it will harden on its own, like portland cement or hydraulic lime.
lift
An individual pass of mortar application into a masonry joint. Pointing a joint usually takes three lifts, the last being the pointing mortar. Modern term for one layer application of mortar in a joint. Often mentioned in conjuntion with a common construction edict "put in the next lift after its thumb print hard," but basically this recommendation is a recipe for disaster.
poultice
Absorbent, porous material soaked in a liquid that onto a surface to draw out salts or stains. When placed onto a surface the liquid is absorbed in, then porous material draws the liquid back out.
render
A type of stucco exclusively applied to masonry walls.
repointing
The process of refilling a masonry joint with mortar after being cleaned and dressed properly. Mortar between bricks gradually erodes away from the face over time, and eventually repointing is required.
slaking
The process of reintroducing molecular water into fired (or calcined) lime.
sulfate crusts
Gypsum deposits on the surface of a material resulting from the reaction of atmospheric sulfuric acid with lime-bound materials.