I'll tell you right here, as it will help anybody else who wants to make textures.
Saltpeter Crystal: A white crystal.
Sulfur Crystal: A yellow crystal.
Stele: A dark grey or black knife. think of the texture for the iron knife or the athame in tekkit, and then make it dark grey or black.
Alchemical Decoder: It looks a bit like a magnifying glass, but with runes inscribed around the edge, and with green tinted glass.
Runestone: A grey stone with runes on it.
Mana Infuser: Brownish colored, with purple stars at the corners, and a yellow spiral design on top.
Arcane Researcher: Reddish colored, with symbols for each of the elements (fire, water, earth, air) at the corners, and a rune on top.
Mana Enchanter: Like a regular enchanting table, but brownish (same color as the Mana Infuser) and with purple stars at the corners.
Arcane Enchanter: Like a regular enchantment table, but reddish (same color as the Arcane Researcher) and with black spirals at the corners.
Interesting. Is it a forge mod? if so, the forge ore dictionary would allow my mod to use its saltpeter and sulfur, and vice versa. As for the gunpowder recipe, that's how gunpowder was actually made in medieval times, so I just used that. Alchemy may be magic, but it is also a form of proto-science. A lot of the recipes are either based on or the same as they would be in real life.