Calcium sulfate worked example

In a subsequent work, Raff used the CIE system to quantify the colors that could be obtained when using FD C aluminum lakes as colorants in tablet formulations [43]. He reported on the concentration dependence of the tristimulus values obtained when calcium sulfate dihydrate was compressed with various amounts of FD C Blue No. 2 aluminum lake, and one example of the reported data is found in Table 1. 

On the other hand, it is likely that most reactions of silica and silicates in aqueous solutions do involve a temporary expansion of the coordination number from 4 to 5 or 6. Also in certain crystalline silicates, the silicon atom is coordinated with six oxygen atoms, for example, in thaumasite (82). This was also confirmed by Edge and Taylor (83). who worked out the structure of this calcium silicate sulfate carbonate crystal and demonstrated the presence of Si(OH), " ions. 

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