If you put chalk under a powerful microscope—white cliffs of Dover type chalk, not the modern blackboard variety—you will see something like this Because it's not just a rock. It's an accumulation of ancient skeletons: the armored husks of single-celled, ocean-dwelling plankton

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image showing If you put chalk under a powerful microscope—white cliffs of Dover type chalk, not the modern blackboard variety—you will see something like this Because it's not just a rock. It's an accumulation of ancient skeletons: the armored husks of single-celled, ocean-dwelling plankton

affectionateclass on July 27th, 2018 at 18:37 UTC »

cant decide if this is the most interesting thing i've ever seen or the thing that's gonna invade my nightmares forever

WallyJade on July 27th, 2018 at 19:33 UTC »

Is each "sphere" a plankton, or is each oval-shaped "panel" on the spheres the plankton?

jayd00b on July 27th, 2018 at 19:59 UTC »

For anyone interested these are Coccolithophores. They are a type of diatom, a subclass of silica-based microalgae.

Source: Underwater acoustics researcher who got sucked into this bullshit sediment characterization project

EDIT: They are not diatoms. See below.