Magnesium Hydr oxides

4 MgO from Johnson Matthey Properties High purity, mean particle diameter 3 pm [902], 

Only value, data points not reported. Inflection point is also reported. 

9 MgO from Unknown Commercial Source Water-washed, and dried at 110°C 

2 Mg(OH)2 from Ceddar Hill, Purchased from Ward Properties 0.13% SiO2, detailed analysis, SEM images available, BET specific surface area (ground powder) 9.2 mVg [507]. 

PZC/IEP of MgfOHljfrom Ceddar Hill, Purchased from Ward 

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The weathering of surface rocks has had a critical role in the chemical evolution of the continental crust for most of the Earth s history. In the presence of air and water, mafic minerals tend to rapidly weather into iron (oxy)(hydr)oxides, clays, and other silicate minerals, and at least partially water-soluble salts of alkalis (sodium and potassium) and alkaline earths (calcium and magnesium). In contrast, quartz in felsic and intermediate igneous rocks is very stable in the presence of surface air and water, which explains why the mineral readily accumulates in sands and other sediments. 

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