diatomious earth for filters and other uses.

Yes, centric diatom are algae that are species that display radial symmetry. Diatoms are like clams, they have a two-part silica cell wall, called frustules. Diatoms are then divided into two groups based on the symmetry of their frustules, bilaterally symmetrical are called pennate diatom and centric diarom are radial symmetrical.

By rubber, low-density, diatom polyethylene, diatom frustules (largely silicic acid), and PFTE (Teflon).

Diatom exoskeletons, or frustules, are made from silica. To get a clearer insight into this material Go to the related link (AFM maps the diatom exoskeleton) below.

According to SOWPODS (the combination of Scrabble dictionaries used around the world) there are 9 words with the pattern ---STU---. That is, nine letter words with 4th letter S and 5th letter T and 6th letter U. In alphabetical order, they are:

blastulae

blastular

blastulas

caestuses

dyestuffs

frustules

moistures

orestunck

outstunts