Good god. Can someone help me think of what these things are called that I'm thinking of?

Basically I was telling my boyfriend that his eyes reminded me of these things but I couldn’t think of what they were called and I’ve searched a million different terms on google I thought would be relevant and might turn up what I’m looking for but I still can’t find it! Come on interweb.

Anyhow, they are these pools of water, like big puddles maybe, that are very bright colors. Like the edges of the pools are bright orange, then bright green then the rest is a clean bright blue. Maybe a few other colors thrown in there. I felt like they might have something to do with geysers, or sulfur, but I’m not finding anything. They’re really beautiful…I’ve seen photos of them in random places but now that I’m looking for one I can’t find anything.