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.
On the Mohs scale of hardness Emeralds can range from a 7.5 to an 8. The emerald s green color is caused by the presence of chromium and iron. Emerald is a variety of green beryl whose chemical formula is Al2Be3Si6O18. Most of the world s emeralds are found in Columbia, Brazil, and Zambia.