Magnesium , refractive index

Magnesium hydroxide is white, has an average particle size of 1—10 p.m, density of 2.36 g/mL, refractive index of 1.58, and Mohs hardness of 2.00. Water loss on ignition is 31.8 wt %. Magnesium hydroxide contains 1.0 wt % Ca(OH)2 and is made by Solem Industries and Morton Thiokol (25). 

The residue comprising chiefly cyclopentylacetonitrile is washed with dilute hydrochloric acid to remove any amine which may have been formed during the hydrogenation process, and the organic residue comprising cyclopentylacetonitrile is dissolved in ether, the ether solution dried over anhydrous magnesium sulfate and distilled. The cyclopentylacetonitrile boils at 185° to 187°C and has a refractive index of no = 1.4456. 

The dibasic magnesium phospate trihydrate is a white crystalline powder orthorhombic structure refractive index 1.514 density 2.123 g/cm at 15°C melts at 205°C losing a molecule of water decomposes between 550 to 650°C slightly soluble in water soluble in acid insoluble in ethanol. The heptahy-drate MgHP04 7H20 constitutes white monochnic needles density 1.728 g/cm3 at 15°C sparingly soluble in water (3g/L at 20°C) soluble in acids insoluble in ethanol. 

Spinel is a colorless magnesium aluminate (MgAl204) of cubic structure. It is hard and durable, but, like white sapphire, it is not a good diamond substitute because it has a low refractive index and lacks brilliance. However, it is readily doped to produce other gems of various colors. Artificial ruby, for example, is often natural red spinel, and most synthetic blue sapphires on the market are actually blue spinel. 

Filler Opacify compound, increase hardness, reduce cost Changes refractive index and reflective properties, adds bulk to compound Calcium carbonate, magnesium carbonate, barium sulfate, carbon or glass fibres... 

With a density of 1.18gcm-3 the material (solid, non-filled material) will sink in water and float in saturated, magnesium chloride. This material is an amorphous, thermoplastic material whose natural color is a very clear, water-white and so a very wide range of both clear and transparent colors is possible. Has a refractive index of approximately 1.49 and can transmit about 92% of visible light Abbe number is 58. 

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