Celite is a diatomaceous earth. Elemental composition is around this one (Fluka, Celite 501):
Al2O3, 4.0%
CaO, 0.5%
Fe2O3, 1.3%
Na2O + K2O, 3.3%
SiO2, 89.6%
There are various marks of Celite available from Fluka, which differ pH (<7>8.5, pH of 10% slurry in water), particles size (13 micrometer to 130), and how was it treated (acid washed, calcined, Na2CO3 treated).
some types of Celite are not stable towards TfOH (gives Ca(OTf)2 etc.)
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