Onyx Ore –
Onyx ore is the most common of the Nether ores. It is basically the Iron of the Nether. It generates up to level 100 in deposits of eight ores, so you should have no problem finding it. It can be used to make a tool set, an armor set, and a decorative block.
The ore, tool set, armor set, block and gem can be seen in the picture.
Soul Ore:
Soul ore is the main component in making a successful Soul Furnace which is used to Forge spawn eggs. This ore is found in deposits of soul sand, and can be mined for one soul, which can then be used with a bucket of blood for a soul in a bucket of blood.
The ore also serves as a light source.
The ore and soul are shown in the picture.
Nether Crystal Ore:
Nether Crystal is the most powerful of the Nether ores, therefore It is the rarest of them. When mined the ore will drop one Nether Crystal, unless you have Fortune or the Silk Touch, in which case it will give you more gems or the ore respectively. The ore generates to level 100 like onyx, but is six times as rare. It can be used to make an armor set, a tool set, and a decorative block.
Due to the material being heavy, the tool set can only be crafted with Nether Quartz sticks, which can be made from putting eight Nether Quartz around a stick in a crafting table.
The Crystal, ore, tool set, armor set and block can be seen in the picture.
Glowing Ore:
This ore can be mined for a glow shard, or with the Silk Touch as a fancy source of light. The glow shard can be crafted into six Glow Stone Dust or put on top of a stick for ten torches.
The ore can be found in deposits of Glow Stone, but is moderately rare.
The Glowing Ore and the Glowing Shard can be seen in the picture.
Nether Metal Ore:
This is a very strong, rough material. It can only be used for tools because it is too rough for armor. The ore can be found about as much as onyx, but generates in smaller deposits. It can be smelted to obtain one Nether Metal Ingot.
The ore, blocks, tools and ingot can be seen in the picture.