Alchemy can be an important part of a fantasy game system, especially if one of the adventuring player characters actually possesses the skill.  The following provides some guidelines that can help GMs arbitrate what an alchemist can produce or new formulas he/she can create.  Gunpowder, due to game balance, cannot be created. 

New Alchemical Formula Research/Devotement: Like researching spells and rituals, producing new alchemical formulas is a time-intensive process that requires a laboratory, the Alchemy Non-weapon skill, and a place in which to work. 

Laboratory:  these laboratories come in two flavors, basic (300 gps value) and masterworked (500 gps value); the latter contains extra equipment and takes a full 10x10 room to set up.  Masterworked laboratories provide a +2 to Alchemy skill checks.  Magical Laboratories do exist but have limited uses, as they cannot be used to make ‘magical’ Alchemy materials such as potions.  Producing soap, acid, or similar ‘non-magical’ products can benefit from a magical laboratory that grants a +4 to Alchemy rolls.

Alchemy Skill function (OPTIONAL): As a general rule, D4 in Alchemy skill allows the creation of Tier 1-3 alchemy products (most non-magical functions, and mundane cleaning chemicals, perfumes, and soaps), D6 can produce Tier 4, D8 = Tier 5, D10 = Tier 6, and D12+ Tier 7.  Of course, skill checks are still required for success.