The Emerald Eye is a crater that is part of Lakagigar in the Highlands.

When going here, keep in mind that there are a few river crossings. Do not attempt to cross them if you do not feel comfortable or don't have experience. There are parts here with bad cellular connection so it's not the best area to get into trouble. But if you have a proper 4x4, you should be fine. The easiest way to get here is to pass Fjaðrárgljúfur canyon and continue to Laki.

The colours of the crater (and this whole area) really depend on the conditions, so consider a wet or rainy day (or just after the rain) for rich vibrant colors of the moss. The moss is a simple organism that doesn't have roots, so it takes all the humidity from the air, this means it pops with green during rainy days.

Here is a bit more context on Lake:

Laki, a volcanic fissure in Iceland, erupted violently over an eight-month period between June 1783 and February 1784. The eruption spewed out massive amounts of basalt lava and poisonous gases, leading to the death of over 50% of Iceland's livestock and causing a famine that killed at least a fifth of the human population. The aftermath also caused a drop in global temperatures, affecting regions as far as Europe, Africa, and Asia. This natural disaster left a lasting impact on the environment and populations across the globe.