SRD:Quintessence

You collapse a bit of time from the continuum, forming a 1-ounce dollop of thick, gooey material called quintessence. This substance shimmers like a silver mirror when viewed from some angles but is transparent from other viewpoints. You can smooth a dollop of quintessence around any extremely small object.

Objects sealed within quintessence are protected from the effects of time; in practical terms, they enter a state of stasis. Living flesh with only partial contact with quintessence is also partially pulled out of the time stream (the manifester is immune to this effect). This disruption deals 1 point of damage per round beginning 10 rounds after partial contact occurs.

Quintessence can be manually scraped away from a protected object, freeing it to rejoin the time stream. When you do this, there is a 75% chance that the quintessence evaporates back into the continuum. Otherwise, it coalesces again into a 1-inch-diameter bead, available for later use.

Large quantities of quintessence could theoretically be gathered to preserve large items or structures (or even a complete living creature; if completely immersed, a living creature would not take the damage associated with partial contact). However, psionic characters and creatures are generally loath to do so because accumulations of quintessence weighing 1 pound or more hinder psionic activity within a 5-foot radius of the accumulation: Powers require twice as many power points to manifest, unless the manifester makes a successful Will save (DC 16) each time he or she attempts to manifest a power. Also in these circumstances, manifesting a psi-like ability that is usable at will is a full-round action rather than a standard action.