Acid washed sand

[Dr Engelbert Buxbaum]

keaboletse Moemedi wrote:

>  I do not have a commercial
> sand but i want investigate the pigment of phytoplankton in surface
> water. Please advice me how to prepare the sand which is not
> commercially prepared.

The usual way to do this is to boil sea sand (mostly SiO2) with
hydrochloric acid to remove acid-soluble contamminants (in particular
calcium carbonate) and then glow it to destroy organic matter.