I muttered and got the remaining fifty out of my pocket, shredding it and tossing it in to complete the potion.
The next step was where the effort came in. Once all the ingredients are mixed together, you have to force enough energy through them to activate them.
It isn't the actual physical ingredients that are important—it's the meaning that they carry, too, the significance that they have for the person making the potion, and for those who will be using it.
The energy from magic comes from a lot of places. It can come from a special place (usually some spectacular natural site, like Mount St. Helens, or Old Faithful), from a focus of some kind (like Stonehenge is, on a large scale), or from inside of people.
The best magic comes from the inside. Sometimes it's just pure mental effort, raw willpower.
Sometimes it's emotions and feelings. All of them are viable tinder to be used for the proverbial fire.
