A Window Into Spiritual Practice - The Manipulation of Mental Essences and Others
Before I continue, a brief note: essences will sometimes become colored by the nature of their source. Physical essence drawn from wood or metal might feel sticky and tasteless, while physical essence drawn from a person or animal will feel more "alive," buzzing with potential. Conscious essence often carries a strong influence of one or more senses, which can give the working a glamour or even deceive those interacting with it. Mental essence often carries a notion or a strong feeling, making those who interact with it experience intrusive or spurious thoughts, or feel stronger or more conflicting emotions.
Mental Essence takes a lot of features when I use it, but I generally work it into yellow or white light, golden flames, or glimmering strands. These, like all the other associated descriptors, are nothing more than illusions of the Conscious. The "flames" cannot actually burn any materials, or change the heat of the room. What the essence really is is concentrated willpower, intention; I pour my desire and my thoughts into it. If you were to sense the real nature behind the imagery I've described, what you'd detect is that intent and those thoughts. Say for example, if the working was to cut through someone's stubbornness and help them understand, observing the "blade" closely enough would reveal that that was what I wanted. Mental Essence is kinetic, vivid, and lacks stamina; if committed to a task, it will soon burn out and require replacement. If I weave Conscious and Vital essences into it, I can give it the consumptive property that it needs to draw on more fuel. Even that is not perfect. If Conscious Essence is what I use for "fuel," Mental Essence serves as the "spark plug." The wheels, too, in a sense. It's the "GO" involved. If I worked a "red" disc and used "orange" designs to make it grow into a shield, I would use "yellow" to give it intensity. Instead of letting things dig into it and leave holes, the shield now deflects essential harm. Making one to deflect material objects is, insofar as I've seen, not possible.
Vital Essence is more meta. For starters, I generally work it into green, abstract forms somewhat resembling wind, ripples, or "energy." Sparks, lightning, that sort of thing. That is not the form it takes on its own, which is more like pale fibers, but I don't use it that way. The root of this essence is a sort of manipulative unity, an engineered cohesion. It can make Physical Essence more resilient (in conjunction with Conscious Essence), or less resilient (if working with Mental Essence), or both in various places. It can control how Conscious Essence makes things grow, curbing it or encouraging it in places. It takes the violent, erratic driving force that is Mental Essence, and gives it direction. Purpose. In the above car analogy, Vital Essence is the steering wheel. If a steering wheel allowed you to molecularly manipulate your car. I wire my constructs with "green" to give me more control, but only if I have the time to really make use of it. It takes more time and focus for me, not sure about the rest of you.
Causality, experienced in its "essential" state, is something of a mystery to me. I generally view it as a shapeless, blue field, something like light and something like water. I cannot make it take an arbitrary shape, like I can with the other essences, but I can work through it to shape other things. If I use Causality at a low concentration, high emission, it seems almost white to me. That form seems to repel things and is useful for firing off my completed workings with greater "oomph," or forcing excess or unwanted influences out of my being. It's a "release" valve. If I use Causality at a high concentration, low emission, it seems almost black instead. That form I use as a siphon, to draw essences into myself and (if I open the way to the greater Causal Plane) release those essences into the Universe remotely from myself. While I could "fire and forget" that way, I believe consequences will come back my way. So instead, I sort of "bubble" it where I can keep tabs on it, and bring the castoff back later for proper disposal. Causality is also a vector for nonverbal, potentially non-psychic communication, but I'm not as well-versed in that.
There are "higher" forms I have started learning to use, essences more removed from conventional reality, but I know little about them for certain and have nothing specific to speak on. One is tied to the All-Seeing Observer, what some refer to as Ajna or the Third Eye. It is a penetrating sense that needs no baser essences and can ignore/avoid all of them. It is my understanding that a lot of the essences "higher" than this are the exclusive property of enlightened beings or high-energy existences, so my ability to draw on them without earning them is likely limited.