Really, all geological materials are temporal since they all, given enough time and circumstance, will erode and disintegrate. But since that could take millions of years, exceptions are made which categorize some materials as "temporal" and others as more permanent. For instance, drier regions, where any water that falls quickly evaporates, may harbor significant salt deposits. Since salt dissolves in water, it's considered a temporal material, or one that quickly disappears in consistently wet environments, such as the Florida Everglades.
A temporal material may also simply refer to the concept of time as a material. According to linguists at the University of California-Berkeley's Department of Linguistics, while time doesn't manifest itself in the visible sense, it is considered a physical property of the universe. Such consideration is seen in how we measure time via material gauges, such as mechanical clocks and watches. Additionally, in American Sign Language, the way signers use their arms and eyes depicts time as a physical property that can be measured and perceived.
In the human brain, the temporal lobe is responsible for processing auditory and visual information and has a great influence on how we perceive the world and time. Fittingly, then, since it deals with perception of time and activity, it's labeled as a "temporal" material of the brain. Those who experience damage to their temporal lobes may have seizures and impaired ability to accurately perceive distance, shapes and sounds. Additionally, tumors on the temporal lobe may cause hallucinations that affect smell and taste.
Archaeologists have a special interest in temporal materials. When these scientists find temporal materials as they dig in the earth, it means they've found artifacts that have chronological significance. Temporal artifacts give clues as to when they were made in the stream of time. For example, in the book, "Archaeology," by David Hurst Thomas and Robert L. Kelly, the authors refer to a "Type B" temporal artifact as one that was likely made between 500 and 1000 A.D.