The image shows a human blood sample, under direct light (generated using a mobile-phone flashlight). The sample was obtained from the forearm of a student’s hand at Caltech (1200 East California Boulevard, Pasadena, CA) around 11:00 pm local time (CA) on May 30th, 2019. The skin was pierced using a scissor, and the blood was extracted using a wet cotton swab.
Note the fluid-like nature, and the granular continuity of the sample.
#caltechbi1


Location of the piercing.