Hardness (H) - The resistance of a mineral to scratching. Like calcium carbonate, vaterite, aragonite are all different forms CaCO 3. Monoclinic - Denotes a crystal system or three-dimensional geometric arrangement having three unequal axes of which one is at right angles to the other two. Metamorphic - When new minerals form at the expense of earlier ones owing to the effects of changing -usually increasing - temperature or pressure or both on some existing rock type. Sedimentary - When minerals are the result of sedimentation, a process whose raw materials are particles from other rocks that have undergone weathering or erosion. Triclinic - Denotes a crystal system or three-dimensional geometrical arrangement having three unequal oblique axes. Igneous (magmatic) - When minerals crystallize from a melt. Hydrothermal - When minerals are chemically precipitated from hot solutions within Earth. This causes reaction between incompatible ions and changes the thermodynamic and equilibrium state of the source fluid. Supersaturation and subsequent deposition of the inorganic salts occur.Īnhydrous - A substance that does not contain any water.Įlements - May exist in the native (uncombined) state, in which case their formulas are simply their chemical symbols: gold (Au), carbon (C) in its polymorphic form of diamond, and sulfur (S) are common examples. Inorganic scale refers to dissolved minerals that are forced out of solution.

When we speak of scale for the most part, we are referring to inorganic scale. That being said under extreme circumstances they will percipitate out. Please note that calcium sulfate and calcium chloride along with magnesium sulfate and magnesium chloride are considered permanent hardness, which do not precipitate out as temperature increases. Some other common forms of scale are calcium and barium sulfate, magnesium-based scales, silica scales, iron scales, calcium phosphate, and struvite. The main form of scale and most known to everyone is calcium carbonate, but it is not the only form of scale. The formation of mineral deposits is affected by several factors including supersaturation, temperature, pH, pressure, flow velocity, and the presence of impurities.ĭifferent areas and processes, where equipment comes into contact with scaling water either with or without temperature gradient, are being affected by this problem steam generators, cooling systems, membrane surfaces, and evaporators, just to name a few. The primary agents responsible are the carbonates and sulfates of calcium and magnesium with barium salts, silicate, and phosphate scaling. Mineral scale formation is a considerable issue in domestic, commercial, and industrial applications. Scale is the precipitation of mineral deposits that are caused by soluble salts. What is Scale and the Known Types of Scale?

Magnesium carbonate precipitate color