User blog comment:Aptos/Any questions on Gem biology?/@comment-26593284-20160504153119/@comment-27304481-20160504164143

While that is theoretically possible, it is highly unnecesary. The modt likely concept for CG having blood would be to blush and show damage, it would be like a social concept. Actually bleeding would be unnecesary and a waste of energy.

Hoeever, while it is ineefficient and mostly social, it is possible to make fluid light forms of holograms. It would be fairly pointless, but they could waste energy on using the fluid.

If a gem really wante dto be effective, they would use the fluid hydraulically. Have hydrostatic shstems to increase strength in pressure. This would gush out upon injury, and could be this "blood".