Nether Essence
Mod Overview
This is a completely reworked and enhanced version of flayr's Nether Essence mod. This addition introduces a unique substance called Nether Essence into the game, which opens up new possibilities for crafting gunpowder, serves as an alternative fuel source, and allows for the creation of glowing blocks. A special feature of the mod is the function to restore lost items.
Mod Content
The mod adds one new item and two types of blocks. The main element is Nether Essence - a special substance whose primary purpose is to create gunpowder through an alternative method.
To create Nether Essence, you'll need 6 netherrack blocks, 2 soul sand blocks, and 1 magma block (in versions prior to 7.0.2, a lava bucket was used). 
From 4 units of Nether Essence combined with 4 redstone dust and 1 piece of coal, you can obtain gunpowder. 
8 units of Nether Essence can be combined into a Nether Essence block, which emits light. Although its brightness is inferior to glowstone and torches, this block has an important advantage - it's waterproof. 
To create a more powerful light source, you can craft a Radiant Nether Essence Block by surrounding glowstone with Nether Essence substance.

Both types of Nether Essence (both the individual substance and the blocks) can be used as fuel obtained in the Nether. One unit of Nether Essence can smelt 4 blocks, while a whole Nether Essence block can smelt 32 blocks.

Item Restoration Block
After placing the Item Restoration Block, it will begin to glow at a certain point when items in the world have despawned. At this moment, you can activate the block with a right-click, switching it to active mode. After some time, the block will disappear, leaving previously lost items in its place.