Traumatic optic neuropathy (TON) refers to an acute injury of the optic nerve secondary to trauma. The optic nerve axons may be damaged either directly or indirectly and the visual loss may be partial or complete.
In Minecraft, emerald ore is very hard to find and is found in small deposits in the Extreme Hills biome. You can usually find emerald ore between 13 and 31 blocks below the ground and close to lava. So if you see a pool of lava in the Extreme Hills biome, that is a great place to start mining downward.
Emeralds were well known among the people of the Bible lands. One of the earliest known source of emerald were mines located near the Red Sea in Egypt. There is evidence that these mines were in operation as early as 1650 BC (the time that the Hebrew people would have been in Egypt).