The lifesaving secret hidden inside a horseshoe crab's blue blood

There is an episode in Elementary that involves the Horseshoe, its extraction and conservation. It is just a regular episode, but the visual presentation of the extraction was fascinating. I hope they are real. :)

Few things look more cruel and dystopic than the rooms where they harvest the blood of horseshoe crabs

Has anyone on HN gotten the horseshoe crab pin and can share the story?

Go crabs go!