Blood (Earth-2042)

"On the blood of our fathers, on the blood of our sons. We swore to uphold the Covenant!"

- Rtas 'Vadum Blood is a liquid substance present in most sentient and non-sentient beings, though not all species have the same color of blood. Humans, San'Shyuum, and Aqualish, for example, have red blood; while Rodians, Duros, Yanme'e and Trandoshans have green blood. Sangheili and Kig-Yar have purple blood and Ewoks and Jiralhanae have scarlet blood.

By testing a sample of someone's blood, it is possible to get a midi-chlorian count and determine how sensitive one was to the Force. Human blood was said to have a characteristic metallic taste.

Source

 * https://starwars.fandom.com/wiki/Blood.